Aces High Bulletin Board
General Forums => Aircraft and Vehicles => Topic started by: BulletVI on June 01, 2010, 06:47:22 PM
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now dont get me wrong the team at aces high II have done a great job of creating and modeling aircraft within aces high II. But there is one point i would like to point out to them. that is from some of the later war aircraft i.e the tempest the typhoon the P-51 and a few others. now the flight models are great but i feel that the aces team have forgotten one factor about these aircraft.and that is that a typhoon will only start to outclimb a Spit 8 or zero in a 1000 feet per minute climb but above that it wont in real life due to power to weight ratio's of the aircraft. the tempest is heavier than the spit 8 an zero so thus if it climbs more than 1000 feet per minute it looses speed. this is due to a physics factor that i believe they havent forgoten but have kept the same for every aircraft within the game. And that physics factor is GRAVITY. Basics physics dictates that a 1kg object needs 3 times its weight to counteract gravity. now thats a basic rule that all aircraft designers have lived by. and again physics dictates that the heavier the object the more power it needs to overcome gravity at a more accute angle. so i ask can a tempest out clime a spit 8 or a zero at a climb angle of 75 degrees for more than 30 seconds i dont thinkso and im a trained air frames engineer. i also accept that computers and servers and progams wont give you the exact realism you need in a game but sureley even thats not possible with computer programing.
so i would like your opinion on this please as i believe this to be an opened minded subject free to all opinions <Salute> All
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Although I'm not informed on the subject, I would suggest you list your sources to some of the information you're citing.
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Wouldn't Power/Mass ratio be the main deciding factor in this? Assuming speeds are the same.
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The aircraft's power doesn't overcome gravity. The aircraft's LIFT does. Excess power simply helps you climb better. Assuming you can translate that power into excess thrust.
P.S. There is a very big difference between minor zoom climbs and steady climb rates.
Your entire post seems to be lacking in a general understanding of how the differences in airframes dictate different performances.
P.P.S. I've never heard of a zero outclimbing a tempest, but a spit8 blows one away in this game, by a significant margin.
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Thorism have a brother? :D
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Basics physics dictates that a 1kg object needs 3 times its weight to counteract gravity.
Say WHAAAATTTT?
This statement makes no since at all.
physics dictates that the heavier the object the more power it needs to overcome gravity at a more accute angle.
Say WHAAAAAT?
You may wish to get your physics book out because angle of climb has nothing to do with power required.
HiTech
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Thorism have a brother? :D
No but it looks like junior was awake during his science class film and learned something. Problem is that he is taking that data and applying the single plane views of the basic formulas when he needs to educate himself on the 3 dimensional plane of aerodynamics. It also appears that he remains in asleep in english class.
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hitech, I think he's saying that you need more power to keep an airplane moving as the angle of climb increases (the wings won't provide lift when in a 90degree climb).
As for the 1kg thing, I have not a clue what he's talking about. Honestly it reminds me of something about inertia: the formula had a 3 in it :rofl.
Also, I don't buy that part about him being a "trained air frames engineer". Seems like an engineer would have better spelling and grammar.
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hitech, I think he's saying that you need more power to keep an airplane moving as the angle of climb increases (the wings won't provide lift when in a 90degree climb).
As for the 1kg thing, I have not a clue what he's talking about. Honestly it reminds me of something about inertia: the formula had a 3 in it :rofl.
Also, I don't buy that part about him being a "trained air frames engineer". Seems like an engineer would have better spelling and grammar.
The problem is , it does not require more power as climb angle increases only more thrust.
Seems like an engineer would have better spelling and grammar.
You haven't been reading enough of my writing.
HiTech
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actually, if we are getting technical :huh speed creates the lift, thrust is just the way to get the speed. How much speed? Depends on the weight of the aircraft and the airfoil. How much lift is created from those two combined with a certain amount of speed.
:cry i think...now my head hurts. i like , learneded this somewhere,...in like...school or something...ah huh. ahuh huh haha huh.
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Nothing about this...
now dont get me wrong the team at aces high II have done a great job of creating and modeling aircraft within aces high II. But there is one point i would like to point out to them. that is from some of the later war aircraft i.e the tempest the typhoon the P-51 and a few others. now the flight models are great but i feel that the aces team have forgotten one factor about these aircraft.and that is that a typhoon will only start to outclimb a Spit 8 or zero in a 1000 feet per minute climb but above that it wont in real life due to power to weight ratio's of the aircraft. the tempest is heavier than the spit 8 an zero so thus if it climbs more than 1000 feet per minute it looses speed. this is due to a physics factor that i believe they havent forgoten but have kept the same for every aircraft within the game. And that physics factor is GRAVITY. Basics physics dictates that a 1kg object needs 3 times its weight to counteract gravity. now thats a basic rule that all aircraft designers have lived by. and again physics dictates that the heavier the object the more power it needs to overcome gravity at a more accute angle. so i ask can a tempest out clime a spit 8 or a zero at a climb angle of 75 degrees for more than 30 seconds i dont thinkso and
adds up to this.
im a trained air frames engineer.
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You haven't been reading enough of my writing.
HiTech
Word ;)
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Werd ;)
Fixed
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I am not an airframes engineer; but, I play one on TV. I also stayed at a Holiday Inn Express last night. :rofl
This thread makes me laugh. It is funny enough that OP is trying to school HTC on the laws of phyics and flight modeling ('cause I am sure that they completely forgot to account for gravity in the coading) :rofl :rofl :rofl :rofl :rofl ..... ; but, then to read the manner in which it was posted.... I can't help but laugh. Thank you for starting my day with a belly laugh!
Next issue...... If someone is speed reading, at say 90 mph, and slams into a wall of text, the laws of physics and inertia dictate that the readers eyes should pop from his head faster in a Tempest than an A6M or a Spit 8. With that in mind would the injuries be more severe in the late war birds? :rofl :rofl :rofl :rofl :rofl :rofl :rofl :rofl
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The problem is , it does not require more power as climb angle increases only more thrust.
You haven't been reading enough of my writing.
HiTech
Ok now I am confused? What produces thrust or in this case more thrust if not the engine?? I are NOT an engineer :huh
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Ok now I am confused? What produces thrust or in this case more thrust if not the engine?? I are NOT an engineer :huh
Prop pitch ?
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and torque
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"1kg object needs 3 times its weight to counteract gravity."
(http://lollinks.files.wordpress.com/2009/07/o-rly__ruserious.jpg)
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and torque
wouldn't that be only static thrust against the fuselage of the aircraft? not a type of thrust that would actualy help the aircraft, yet a type of thrust that the propeller would have to overcome to move forward?
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Boxboy in physics terms you have a few concepts.
Force I assume you know, this is measured in pounds or newtons. Thrust is a force.
Work is = Force * Distance.
Power = Work / Time.
Speed = Distance / Time.
Solving these equations we also get
Power = force * speed.
So in airplane terms lets ignore drag for a sec.
Once an airplane is accelerated to flying speed it requires no force to continue flying but the plane is still generating lift and hence requires no power to continue flying level but is still generating lift. Now picture a helicopter with no drag, once the rotors are accelerated they would continue to provide thrust/lift with out any power.
Now with drag and flying level all power is simply used in overcoming drag. Power required is force (i.e. drag) * speed.
But the key is the power definition. of Force * speed.
So now to calculate power for climb speed we simply need the weight of object and speed of climb to calculate power required. I.E. Power = Weight * speed.
Horse powers definition is Lifting 550 pounds 1 foot in 1 sec.
But if we put in a gear box or lever we could be lifting 1100 lbs 1 foot in 2 secs with the exact same power.
So angle of climb is all about a propeller and plane design. A helicopter climbing straight up requires no more extra power then an airplane with the same weight if they climb at the same rate.
So to summarize why i pointed the thrust / power out. Not to many engineers would substitute the word power for force when describing what is required for angle of climb.
HiTech
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Don't forget Engine Dynamics young man!!!!
WOW, you're going to get blasted, if you haven't already.
Time to read the replies...... :rock
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Anyone want to make a bet that the "aircraft engineer" OP doesn't post a reply until after school is out and he's finished with dinner/homework?
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Actually..... Rereading him, he states "airframe engineer" but also made it two words.......... :headscratch:
Anyone want to make a bet that the "aircraft engineer" OP doesn't post a reply until after school is out and he's finished with dinner/homework?
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Engineer must be one of the most abused terms of the last century. Do anything slightly technical and you have an instant right to call yourself an engineer.
(http://www.okmag.com/imgUL/Image/2008%20October/tv.jpg)
TV repairman? No - he's a TV engineer!
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Sanitation Engineer
(http://oswaldadventures.files.wordpress.com/2009/07/garbage.jpg)
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Actually..... Rereading him, he states "airframe engineer" but also made it two words.......... :headscratch:
yeah, I caught that too.
when "pretending" to be something, it really helps if you spell it correctly.
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I understand what BulletVI is trying to say though it would help if he provided more specificity (yes that's a word!). HT's responses to BulletVI, I can understand because HT know's what he's talking about. Some of you guys piling on however ....hmmmm ;).
BulletVI:
Your answer lies in understanding the following relationships and as they change with respect to time.
For an ACCELERATED climb (forward airspeed not constant) the forces along the direction of flight can be expressed as:
F = Thrust – Drag – Weight * sin (climb_angle)
Since weight = mass * gravity we can subsitute in the equation above thus becoming
F = Thrust - Drag - Mass * gravity * sin(climb_angle)
In your Tempest, A6M, Spit8 example you were focused on the effect of gravity. The greater the climb_angle, the greater the effect of weight / gravity on the overall forces. But that's only one of variables. Thrust and Drag play a part as well. Ignore them at your peril ;). Be very careful of oversimplifying the dynamics because it will bite you in the butt.
Another way to look at an accelerated climb is this..
Specific Excess Power (Ps) = (T - D) / W * V = (change_in_alt + change_in_airspeed)
Hope that gets you on your way to understanding!
Tango
412th FS Braunco Mustangs
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Thanks Hitech for clearing that up, it has been a long time since I really thought about math problems and such. I completely forgot about levers, pullys, and such and their effect on things for the same effort.
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Hope that gets you on your way to understanding!
I strongly doubt it.
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All I know is no matter what plane I pick, I never can climb up fast enough to an enemy before he gets me in his dive, or catch up to bombers. Stall it every time. Course I wuz a ground grunt so flying the planes is just plain fun for me.
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Word ;)
I know you really meant...."Werd".
edit: sorry, I see I was a little late on that one
Bottom line is someone is confusing potential vs kinetic....back to my cave...
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Gotta say I've enjoyed reading the boards a lot more ever since HT started talking physics with other aerojunkies.
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Say WHAAAATTTT?
HT been watching maury povich again
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Gotta say I've enjoyed reading the boards a lot more ever since HT started talking physics with other aerojunkies.
You junkies are all the same, always looking for your next hit. :neener:
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:huh
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Gotta say I've enjoyed reading the boards a lot more ever since HT started talking physics with other aerojunkies.
You truly are a sick man, I suggest you seek help :) :D
HiTech
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Also, I don't buy that part about him being a "trained air frames engineer". Seems like an engineer would have better spelling and grammar.
That's a foolish thing to say :(.
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Its foolish to think a man with a degree and who is a trained engineer to use spelling and grammar above the level of a 10yr old?
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Amazing, the OP hasn't responded since his original post claiming to be an "air frames engineer".
His mother must have grounded him from the computer.
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Ok now I am confused? What produces thrust or in this case more thrust if not the engine?? I are NOT an engineer :huh
I guess you could argue that the prop creates the thrust. But the engine is what spins the prop. So you WOULD need a more powerfull engine to keep a plane moving forward (from the pilot's point of view) as the angle of climb increases.
You would need a power to weight ratio of at least 1:1 to maintain your current velocity at a 90degree angle of climb (strait up), and at least 1.00000000000..........1 :1 to accelerate (however slowly) when in a 90degree angle of climb.
Just saw this and had to answer it, sorry.
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What about prop pitch Nemesis? No pitch whatsoever and the engine could churn out 15,000hp and get nothing more than a good whirring noise. Too much pitch and the thing would only roll to one side, like a paddle boat wheel. Obviously no prop, no go. Put a prop on with the right pitch and less horsepower is required to create thrust.
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Yes, but I would group that with the prop. The engine is what is doing the real work. Just as you could have an engine spinning a blade with no pitch and get no forward movment, you could have a rubber band spinning a prop optimized for maximum thrust (starting from 0mph) and still get no forward movment.
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You would need a power to weight ratio of at least 1:1 to maintain your current velocity at a 90degree angle of climb (strait up), and at least 1.00000000000..........1 :1 to accelerate (however slowly) when in a 90degree angle of climb.
Just saw this and had to answer it, sorry.
:huh Please correct your answer ;). It's not good to confuse people.
Tango
412th FS Braunco Mustangs
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Nemisis: You are randomly interchanging words thrust and power.
You need a THRUST to weight ratio of 1. The POWER required for any climb angle is NOT really a consideration.
HiTech
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Yeah, it was like 11 o'clock where I live. You're lucky I was still forming coherent scentences by that time :devil.
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Yeah, it was like 11 o'clock where I live. You're lucky I was still forming coherent scentences by that time :devil.
ahhhh, but you weren't! Thats what Hitech was pointing out! :neener:
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I was coherent, I was just confusing my terms by that time. If I had made that post at, say, 8 o'clock, I would have said "thrust to weight ratio of 1:1".
After about 10, I can't think strait, and after 11, I'm lucky to make any sense what so ever.
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This thread make me think of something: The F16 is unique as, if I'm understanding correctly, it's thrust at burner actually eXCEEDS the weight of the jet? So...it can accelerate going straight up. What propeller-driven craft has come closest to that?
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This thread make me think of something: The F16 is unique as, if I'm understanding correctly, it's thrust at burner actually eXCEEDS the weight of the jet? So...it can accelerate going straight up. What propeller-driven craft has come closest to that?
Any helicopter.
HiTech
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bahhhh
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:rofl :rofl :rofl :rofl
Don't forget the Osprey.
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FYI the F15's had a much higher than 1 -1 thrust to weight ratio.
Could go from deck to 60k straight up on afterburner.
From Wiki
Fighters
F15C 46,900 (2) each engine each producing 46,900 lbs of thrust.
Aircraft weight, full fuel, 51,023
Max takeoff load 81,000
Thrust to weight full fuel 1.14
As fuel burned it would just get better.
F-15K F-15C Mig-29K Mig-29B F-22
1.14 1.03 1.00 1.15 1.14
I believe the F14 would do similar.
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Any helicopter.
HiTech
cruel :)
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FYI the F15's had a much higher than 1 -1 thrust to weight ratio.
Could go from deck to 60k straight up on afterburner.
From Wiki
Fighters
F15C 46,900 (2) each engine each producing 46,900 lbs of thrust.
Aircraft weight, full fuel, 51,023
Max takeoff load 81,000
Thrust to weight full fuel 1.14
As fuel burned it would just get better.
F-15K F-15C Mig-29K Mig-29B F-22
1.14 1.03 1.00 1.15 1.14
I believe the F14 would do similar.
F-15K hmm going to have to look that one up.
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I was coherent, I was just confusing my terms by that time. If I had made that post at, say, 8 o'clock, I would have said "thrust to weight ratio of 1:1".
After about 10, I can't think strait, and after 11, I'm lucky to make any sense what so ever.
You use a shovel to dig that hole?
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Ok now I am confused? What produces thrust or in this case more thrust if not the engine?? I are NOT an engineer :huh
The Propeller creates the thrust (on a prop plane).
When the propeller on the aircraft engine rotates, it pulls in air from in front of the aircraft and pushes it back towards the tail. The force generated by this action is called "thrust". Thrust gives the aircraft forward momentum, and in turn, creates lift on the lifting surfaces (mainly the wings). Generally, the greater the thrust, the greater the airspeed. Thrust is controlled by raising or lowering the revolutions-per-minute (rpm) of the engine by using the throttle.
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wait, wait........u lost me at "propeller" :huh
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Thrust is controlled by raising or lowering the revolutions-per-minute (rpm) of the engine by using the throttle.
Or by increase toque on the prop along with increasing the pitch of the prop. I.E. constant speed props.
HiTech
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Or by increase toque on the prop along with increasing the pitch of the prop. I.E. constant speed props.
HiTech
Correct, sorry Dale for not including that. :rock
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Yes, but the prop is just a tool utilized by the engine.
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Yes, but the prop is just a tool utilized by the engine.
Stop digging.
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Yes, but the prop is just a tool utilized by the engine.
....and you're nothing more than a squeaker with a troll's figure. If you cannot understand my simple Physics lesson and HT's addendum, then take a Physics class.
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This thread make me think of something: The F16 is unique as, if I'm understanding correctly, it's thrust at burner actually eXCEEDS the weight of the jet? So...it can accelerate going straight up. What propeller-driven craft has come closest to that?
The F-16 isn't unique in that regard, btw. ;)
Anyways, when talking about fixed wing prop driven aircraft...two quickly come to mind; Turbine Toucan and Turbo Raven. Both are (were in the case of the Raven) one off jobs. Well, Turbine Toucan is basically modified Pitts Model 12 with turboprop powerplant.
They are promising close to 1.65:1 thrust to weight ratio in airshow weight.
http://www.turbinetoucan.com/homepage/ (http://www.turbinetoucan.com/homepage/)
Pretty hilarious ride I'm sure. :)
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See Rule #4
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wow, I wasn't disagreeing that thrust is produced by the prop. I was simply saying that if you want more thrust, you must make the prop spin faster (assuming a fixed pitch prop), and that would be done by the engine.
You do realize that spinning the prop faster might actually produce less thrust right? This is especially true for a fixed pitch prop.
Tango
412th FS Braunco Mustangs
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Thats true... once it reaches a certian speed (not sure of what speed though). But I guarantee that a prop spinning at 100rpms will generate more thrust than one spinning at 50rpms. I know physics (sort of), but I have a terrible head for numbers.
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Thats true... once it reaches a certian speed (not sure of what speed though). But I guarantee that a prop spinning at 100rpms will generate more thrust than one spinning at 50rpms.
Not necessarily. It's all about the blade relative angle of attack which is greatly influenced by the vector sum of forward airspeed and prop rotational speed. This is often represented by propeller advance ratio:
J= V/n*d
Where V = airspeed, n= prop rotation, d= prop diameter
Advance ratio is usually plotted against propeller efficiency like this:
(http://www.allstar.fiu.edu/aero/images/e1low.gif)
For a fixed pitch propeller there's a maximum efficiency that is attained by a combination of V/n*d. You adjust this for airplanes with fixed pitch props in flight two ways, either by airspeed or by rpm's. It's a balancing act of velocity and rpm where raising or lower rpm is needed to maintain max efficiency thus max thrust. Higher RPM does not = higher thrust automatically.
Tango
412th FS Braunco Mustangs
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Yes, but the prop is just a tool utilized by the engine.
The prop is there to keep the pilot cool. If you don't think so, make it stop turning, and watch him sweat! :t
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hmmm... point taken. Still, there is a limit to how much altering the pitch of the blade will do. Eventually you will have to make it spin faster, or cram more engines onto your aircraft. Props to have limits, which is why we have jets.
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Props tend to get longer and have more blades to handle more power.
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wow, I wasn't disagreeing that thrust is produced by the prop. I was simply saying that if you want more thrust, you must make the prop spin faster (assuming a fixed pitch prop), and that would be done by the engine.
Are you pissed because your wife kicked you out?
My wife and I are happily married. So what does my marital status have to do with the fact that you have no clue about Physics? Your statement on the engine is STILL incorrect.
Your arms look tired, put the shovel down and listen (read).
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dtango, your mixing efficiency with thrust.
Eff = (Thrust * Speed) / Power
Nemisis statement of more rpm = more thrust is almost always correct unless a prop has a very large blade angle of 30 degrees or more and traveling at very slow speeds.
HiTech
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dtango, your mixing efficiency with thrust.
Eff = (Thrust * Speed) / Power
Yes, but thrust = power * eff / speed no? Thus the amount of thrust is also a function of prop efficiency which depends on rotational velocity as a component.
Nemisis statement of more rpm = more thrust is almost always correct unless a prop has a very large blade angle of 30 degrees or more and traveling at very slow speeds.
HiTech
Agreed. Perhaps I'm being too pedantic on my part in responding to Nemisis :). Point taken.
Tango
412th FS Braunco Mustangs
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Yes, but thrust = power * eff / speed no? Thus the amount of thrust is also a function of prop efficiency which depends on rotational velocity as a component.
Try using this equation standing still.
HiTech
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Try using this equation standing still.
HiTech
:D Thanks for throwing in a monkey wrench and pointing out the static thrust case to mess me up, but you're right and have made your point!
Tango
412th FS Braunco Mustangs
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Basics physics dictates that a 1kg object needs 3 times its weight to counteract gravity. now thats a basic rule that all aircraft designers have lived by.
Three times it's weight of what? If it had three times its weight in gold, it could probably buy a ride on a better-climbing aircraft. That'd work. :aok
As for this rule, I don't remember it from my aircraft design classes at Michigan or Stanford but that was a long time ago, admittedly.
However, Bullet, here's the real problem with HTC: it spends all its people's time on things like bug fixes and dry subjects that guys who wear straight-legged gray suit and thin ties care about. None o' that old-timey stuff is going to get you some clunge at the local watering hole and that why these people are so cranky. If they weren't so cranky, they'd be spending more time on things that are cool.
So, are you with me on this? I ask because I'm about to reveal my triple-nought secret for how you make Aces High into the kind of Red Hot Dyma-no that'll really get people's motors humming.
The answer: we need some updates that are REALLY COOL.
The best idea so far: we need a cockpit desktop assistant that pops up on-screen when it senses you're having some issues in flight. It'll look just like the Fonz from Happy Days, complete with the comb and leather jacket. Frequently, and just sort of out of the blue, you know, just to keep the spontaneity levels up there, it'll loudly give you a thumbs up and go, "aaaaaaaay". If you're lucky, it'll climb aboard a vintage Triumph motrocycle and jump a shark.
Now all of that may not seem to be too related to WWII air combat... but that kind of defeatist talk ignores the thing they both have in common: the Fonz and WWII dogfighting - what could be cooler than that?
'member: ever who opposes the evil klowns is ma' emmaknee! Tha evil klowns will nevah dah!
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dtango, your mixing efficiency with thrust.
Eff = (Thrust * Speed) / Power
Nemisis statement of more rpm = more thrust is almost always correct unless a prop has a very large blade angle of 30 degrees or more and traveling at very slow speeds.
HiTech
The discussion (between dtango and I anyway) had some what shifted to prop efficency (kind of).
Rhino, even so, there is a limit to what props can do. You will eventually end up with something resembling the blade assemblies (props?) from a turbofan minus the casing (I'm guessing it won't turn out too well, else they would have done it), or with planes (fighters) 15-20ft off the ground.
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I have browsed, scanned actually, (didn't pay attention at all) all of the aeronautical engineering quandaries. I have been enlightened about subjects and found answers to questions I have yet to ponder. Yet I am still confused. I think the underlying question, which if answered could change the shape of the world, is:
What is the airspeed velocity of an un-laden African Swallow?
And when will two said swallows carrying a coconut by the husk be modeled into the game. :bolt:
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I have browsed, scanned actually, (didn't pay attention at all) all of the aeronautical engineering quandaries. I have been enlightened about subjects and found answers to questions I have yet to ponder. Yet I am still confused. I think the underlying question, which if answered could change the shape of the world, is:
What is the airspeed velocity of an un-laden African Swallow?
And when will two said swallows carrying a coconut by the husk be modeled into the game. :bolt:
Are you suggesting coconuts migrate?
sorry...I won't hijack this thread any further but I couldn't pass this up. :P
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We have aircraft? :headscratch:
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I don't believe that you can prove that african swallows ever entered combat in WWII, thereby eliminating this particular wish.
As to their speed either laden or unladen, well, thats one for the grognards to argue over.
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But the questions begs itself: "It's a simple question of weight ratios. How does a 5 ounce bird carry a one pound coconut?"
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But the questions begs itself: "It's a simple question of weight ratios. How does a 5 ounce bird carry a one pound coconut?"
Carefully!!! :devil
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I really need to watch the Holy Grail again <sigh> :D
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The discussion (between dtango and I anyway) had some what shifted to prop efficency (kind of).
Rhino, even so, there is a limit to what props can do. You will eventually end up with something resembling the blade assemblies (props?) from a turbofan minus the casing (I'm guessing it won't turn out too well, else they would have done it), or with planes (fighters) 15-20ft off the ground.
The problem, I think with the exposed turbofan had more to do with noise < a big bugaboo in civil aviation now>
than efficiency. There is a reason most everyone has gone to high bypass turbofans from the early screamers...well
two actually. First is fuel efficiency and secondly noise reduction.
I will say the loudest general aviation bird I ever heard inflight was the Piaggio Avanti turboprop.
(http://www.aerospace-technology.com/projects/piaggio/images/1-private-jet.jpg)
You could hear this thing for miles, even upwind. Since I started out listening to Lear 23s and Vickers
Viscounts, the Avanti is a real shocker these days. :D Ok, actually I spent some time listening to Phantoms
first, but they were 60s era military, so they don't count :lol
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In combat, it doesn't really matter if your enemy hears you coming when you're pulling 368 at sea level, IMO. He's just as dead if a 1k bomb lands in his foxhole as he is if it lands at his feet.
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ah but as i have seen in the game when you climb to altitude the manifold pressure doesn't drop it remains constant. For example once the Spitfire Mk 16 reatchs an altitude of 18,000 feet its manifold pressure drops so low that the pilot has to boost the engine power by using Wep power to increase performance at and above this altitude. The same go's for the P51 P38 and All other aircraft designed to fly above 18,000 feet. And Also the design of these aircraft are limited to better roll and dive and climb rates above these altitudes. as any no brainer can pick up a book and read the performance spec's on the aircraft. So in conclusion the Spitfire mk16 shouldn't roll and turn as-well as the Spitfire mk 8-9 at low altitude.
and i have even heard from some players who have played the game for years since day 1 say the same , if not something similar along the same lines.
oh and by the way i didnt sleep through English i never learned it I learned Scottish :) :x :lol :lol :lol :lol
Now its understandable that HiTech Cant get everything right as we all know there is no computer system out there yet that can provide the power needed to make any flight sim 100% realistic.
But is it possible to look into reprogramming some planes that need to be sorted through lack of performance that they should have.
Oh an please can they create the Spitfire Mk 8 CV Its Cliped wing like the mk16 but was used by the Australians , New Zealanders And Some Army Air Corps pilots against the Japanese. As It was said that the mk 8 CV could almost stay in turn with the Zero longer than any other pacific theatre aircraft. PLEASE
BulletVI
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Boxboy in physics terms you have a few concepts.
Force I assume you know, this is measured in pounds or newtons. Thrust is a force.
Work is = Force * Distance.
Power = Work / Time.
Speed = Distance / Time.
Solving these equations we also get
Power = force * speed.
So in airplane terms lets ignore drag for a sec.
Once an airplane is accelerated to flying speed it requires no force to continue flying but the plane is still generating lift and hence requires no power to continue flying level but is still generating lift. Now picture a helicopter with no drag, once the rotors are accelerated they would continue to provide thrust/lift with out any power.
Now with drag and flying level all power is simply used in overcoming drag. Power required is force (i.e. drag) * speed.
But the key is the power definition. of Force * speed.
So now to calculate power for climb speed we simply need the weight of object and speed of climb to calculate power required. I.E. Power = Weight * speed.
Horse powers definition is Lifting 550 pounds 1 foot in 1 sec.
But if we put in a gear box or lever we could be lifting 1100 lbs 1 foot in 2 secs with the exact same power.
So angle of climb is all about a propeller and plane design. A helicopter climbing straight up requires no more extra power then an airplane with the same weight if they climb at the same rate.
So to summarize why i pointed the thrust / power out. Not to many engineers would substitute the word power for force when describing what is required for angle of climb.
HiTech
AH But HiTech i agree with your post there but in reading it i think there may be 1 factor that has been left out in the game. and that's drag. Now we all know that any object that moves through air creates drag cripe's the human body creates drag as you walk , move or run.
So as-well as drag There's friction and heat built-up from friction which also affects performance.
For example an aircraft flying at 200mph with a surface area of approximate 45" squared can produce drag of up-to 1/3 of its total surface area.
Now at low altitude the air is thicker and at high altitude the air is thinner so at high altitude the drag an aircraft produces is lower due to the thinness of the air. but at low altitude its thicker thus the aircraft produce's more drag. again back to the mk16 spitfire its wings where clipped to provided a more stable roll rate at high altitude thus at lower altitudes it was less stable due to the drag coefficient of the clipped wings.
So in the programming of certain aircraft have you left the drag factor out or not got it quite right by forgetting that at low altitudes an air craft produces more drag than at higher altitudes.????
Now that's just a thought.
BulletVI
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Bullet wrote:
AH But HiTech i agree with your post there but in reading it i think there may be 1 factor that has been left out in the game.
I'll get right on that and add drag to the sim. How could I have forgotten such a basic concept.
As for your manifold press posting.
Do some real testing, you will find out the manifold pressure starts to drop at their critical alts on all planes .
HiTech
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Bullet wrote:
I'll get right on that and add drag to the sim. How could I have forgotten such a basic concept.
HiTech
LOL not quite enough sarcasm on that one. :D
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LOL not quite enough sarcasm on that one. :D
Dale must be in a good mood today.
He just winged 'em.
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Dale must be in a good mood today.
He just winged 'em.
Careful kid...the next shot's gonna hit it's mark. :rofl
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I'll get right on that and add drag to the sim. How could I have forgotten such a basic concept.
and when you're done with that, we need lift, and gravity!
hitech, you suck!
:rofl :rofl :rofl
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kvuo75, don't forget, he still needs to model the damage from taking a 75mm cannon shell in your cocpit.
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AH But HiTech i agree with your post there but in reading it i think there may be 1 factor that has been left out in the game. and that's drag. Now we all know that any object that moves through air creates drag cripe's the human body creates drag as you walk , move or run.
So as-well as drag There's friction and heat built-up from friction which also affects performance.
For example an aircraft flying at 200mph with a surface area of approximate 45" squared can produce drag of up-to 1/3 of its total surface area.
Now at low altitude the air is thicker and at high altitude the air is thinner so at high altitude the drag an aircraft produces is lower due to the thinness of the air. but at low altitude its thicker thus the aircraft produce's more drag. again back to the mk16 spitfire its wings where clipped to provided a more stable roll rate at high altitude thus at lower altitudes it was less stable due to the drag coefficient of the clipped wings.
So in the programming of certain aircraft have you left the drag factor out or not got it quite right by forgetting that at low altitudes an air craft produces more drag than at higher altitudes.????
Now that's just a thought.
I'm still laughing at this one. :rofl
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I'm still laughing at this one. :rofl
I like the part where he says that an AC with area of up to 45 sq inches (shades of Spinal tap) can produce drag of up to 1/3 its surface area.
And here I thought drag was a force...
I'm also wondering what constitutes a "more stable roll rate"..?
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I like the part where he says that an AC with area of up to 45 sq inches (shades of Spinal tap) can produce drag of up to 1/3 its surface area.
And here I thought drag was a force...
I'm also wondering what constitutes a "more stable roll rate"..?
I don't even think BulletVI knows.
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Guys guys guys, you've got it all wrong. You're not appreciating the awesomeness of CFD.
Bullet: thanks for treating us to your fantastic CFD analysis though at this point I’m not sure which CFD that is: Completely Fictional Dynamics, Confusingly Faulty Dynamics, or Clearly smurfy Dynamics.
But I digress with having a little humor at your expense. You’ve tossed out some flight model zingers. Here’s the deal- FM zingers are a dime a dozen and people toss them out on here all the time thinking that they’ll get noticed. Don’t fall for that trap! You’ve got to distinguish your FM zinger from the rest of the herd mind you, sort of like the techniques a girl will use to stand out at the Miss Universe Pageant (and it’s more than putting lipstick on a pig…well, you get the idea). What’s the difference maker for FM zingers? Your analytics of course. The ones that really stand out are the ones that are strong analytically.
So here’s a helpful guide in order to construct analytically strong FM zingers. Let’s just look at your manifold pressure statement as an illustrative example how differently you might have approached it analytically.
STEP 1: CLEARLY STATE YOUR HYPOTHESIS
½ of all FM zingers fall off the rails at the start because the hypothesis is unclear leaving the rest of us trying to figure just what exactly is the cause and effect relationship someone is trying to make. You’ve actually did well here because it’s pretty clear what you’re saying about AH manifold pressure. It’s much better than other statements like:
“I got shot down in a Spixteen by a freakin’ Mustang in a turn fight yesterday. That’s impossible! There’s something wrong with the Spixteen or Mustang FM!”.
See, with such a statement it’s totally ambiguous as to what is wrong since the cause and effect is left open to interpretation. What is wrong could be pilot suckage as much as an FM problem but we don't know which. However your statement is clear. I’ll restate it in my words:
HYPOTHESIS: “The AH FM is frapping wrong because it doesn’t model engine manifold pressure change with altitude!”
Well, having a clearly stated hypothesis isn’t enough however. If ½ of all FM zingers don’t have clearly stated hypothesis, that leaves ½ of the other FM zingers that actually do so you still have to go beyond that to stand out analytically so don’t stop there!
STEP 2: SUPPORT THE PRINCIPLE BEHIND YOUR HYPOTHESIS
Sort of a corollary of the Step 1, the 2nd place FM zingers quickly become train wrecks is that the principle behind the hypothesis is not explained or proved. Of the ½ of FM zingers that have a clearly stated hypothesis, only 10% of them actually explain the principle behind the hypothesis. Don’t make this mistake either, otherwise your FM zinger looks just like the rest of them. Remember, the goal is to get noticed! In your manifold pressure case, let’s give you a B+ in your statement because you actually state your principle:
…once the Spitfire Mk 16 reatchs an altitude of 18,000 feet its manifold pressure drops…
Not bad, but it could be better. How? By demonstrating this principle either through aero physics math or with data, or both. How might have this looked instead? Maybe something like the following:
“PRINCIPLE: Piston aero engine performance is affected by the reduction in air density as the altitude increases reducing the manifold pressure of the engine. Superchargers can address this but they too eventually are not immune to decreasing air density. For example the following Spitfire Mk VIII (Merlin 66) flight test data demonstrates this:
(http://www.spitfireperformance.com/jf934climb.jpg)
(courtesy wwiiaircraftperformance.com)
As evidenced by the chart the manifold pressure or “boost” level fluctuates between +18 lbs/sq in to 0 lbs/sq in as altitude and supercharger gearing changes.”
If you can do this with charts, even better. People love charts even if they have no clue what the chart means. It helps to add to your level of credibility and authority! But supporting the principle behind your hypothesis still isn’t enough though. We haven’t sealed the deal yet. After all supporting your principle only gives us an idea that perhaps you know what you might be talking about but it doesn’t do a lick to prove anything yet.
STEP 3: TEST YOUR HYPOTHESIS TO PROVE (OR DISPROVE) IT
This is where the rubber meets the road when it comes to FM zingers! Infact people realize this as much that they rush off from STEP 1 to STEP 3 and totally leave out STEP 2. Don’t make this mistake. STEP 2 is important because it gives you a basis for the principle that you will be testing against in STEP 3. ½ of ½ of all FM zingers with clearly stated hypothesis fall for this trap. Assuming that it hasn’t and that we’re in the 10% that haven’t skipped STEP 2, we’re now ready to do the testing and to demonstrate the hypothesis.
In your manifold pressure case, we’ll be generous and give you a C- for it. It’s hard to tell what kind of testing you’ve done and you make some statements in the affirmative as if you or someone else did but clearly HiTech thinks you haven’t. Why is that? Well you’ve not presented the data of your tests of course! But the trick here is NOT ONLY PRESENTING YOUR DATA, the trick is to do this COMPARED AGAINST YOUR PRINCIPLE IN STEP 2. See a lot people will throw out data in a form of test but not against any principle. And when they do we don't have an inkling of the cause and effect relationship they are trying demonstrate.
Here’s how you could have done this much much better, in fact without even actually flight testing it!
TEST: We’ll examine the Aces High Rate of Climb to see if it demonstrates the similar pattern found like in the actual flight test report listed above. Let’s examine the Spitfire Mk XVI in Aces High. I could have chosen the AH Spitfire Mk VIII to match the figures above but since you were talking about the Spitfire XVI we’ll just do that for the heck of it (Nevermind that the Mk VIII uses the Merlin 66 which is what our Mk XVI uses because it’s really just a Mk IX LF with a Merlin 66. Why are the Brits so confusing anyway???? Centre vs. center, colour vs. color?? Really.). Here’s the published RoC chart compared between a Spitfire Mk IX and Spitfire Mk XVI (WEP Power):
(http://thetongsweb.net/images/roc.png)
Well crap. Sure is funny that the AH rate of climb chart exhibits the similar raggedy lines that the real flight test RoC chart shows, especially as altitude increases RoC decreases. What does this all mean??? Well one possibility is that the AH Spitfires engine power output (and thus manifold pressure) actually does decrease with altitude. Huh, fancy that.
But we all know that AH can’t be 100% right right??? So there must be other possibilities of why the AH FM is screwed up and wrong and the manifold pressure goofed! We just have to go fish for some more data to prove our point or repeat steps 1-3 as necessary until we do!
So there you go, 3 E-Z steps to positively make your FM zinger stand out from the rest of the rabble! I’ll let you go figure out how you can apply this to your “drag” question!
Peace, Out!
Tango
412th FS Braunco Mustangs
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Guys guys guys, you've got it all wrong. You're not appreciating the awesomeness of CFD.
Bullet: thanks for treating us to your fantastic CFD analysis though at this point I’m not sure which CFD that is: Completely Fictional Dynamics, Confusingly Faulty Dynamics, or Clearly smurfy Dynamics.
But I digress with having a little humor at your expense. You’ve tossed out some flight model zingers. Here’s the deal- FM zingers are a dime a dozen and people toss them out on here all the time thinking that they’ll get noticed. Don’t fall for that trap! You’ve got to distinguish your FM zinger from the rest of the herd mind you, sort of like the techniques a girl will use to stand out at the Miss Universe Pageant (and it’s more than putting lipstick on a pig…well, you get the idea). What’s the difference maker for FM zingers? Your analytics of course. The ones that really stand out are the ones that are strong analytically.
So here’s a helpful guide in order to construct analytically strong FM zingers. Let’s just look at your manifold pressure statement as an illustrative example how differently you might have approached it analytically.
STEP 1: CLEARLY STATE YOUR HYPOTHESIS
½ of all FM zingers fall off the rails at the start because the hypothesis is unclear leaving the rest of us trying to figure just what exactly is the cause and effect relationship someone is trying to make. You’ve actually did well here because it’s pretty clear what you’re saying about AH manifold pressure. It’s much better than other statements like:
See, with such a statement it’s totally ambiguous as to what is wrong since the cause and effect is left open to interpretation. What is wrong could be pilot suckage as much as an FM problem but we don't know which. However your statement is clear. I’ll restate it in my words:
HYPOTHESIS: “The AH FM is frapping wrong because it doesn’t model engine manifold pressure change with altitude!”
Well, having a clearly stated hypothesis isn’t enough however. If ½ of all FM zingers don’t have clearly stated hypothesis, that leaves ½ of the other FM zingers that actually do so you still have to go beyond that to stand out analytically so don’t stop there!
STEP 2: SUPPORT THE PRINCIPLE BEHIND YOUR HYPOTHESIS
Sort of a corollary of the Step 1, the 2nd place FM zingers quickly become train wrecks is that the principle behind the hypothesis is not explained or proved. Of the ½ of FM zingers that have a clearly stated hypothesis, only 10% of them actually explain the principle behind the hypothesis. Don’t make this mistake either, otherwise your FM zinger looks just like the rest of them. Remember, the goal is to get noticed! In your manifold pressure case, let’s give you a B+ in your statement because you actually state your principle:
Not bad, but it could be better. How? By demonstrating this principle either through aero physics math or with data, or both. How might have this looked instead? Maybe something like the following:
“PRINCIPLE: Piston aero engine performance is affected by the reduction in air density as the altitude increases reducing the manifold pressure of the engine. Superchargers can address this but they too eventually are not immune to decreasing air density. For example the following Spitfire Mk VIII (Merlin 66) flight test data demonstrates this:
(http://www.spitfireperformance.com/jf934climb.jpg)
(courtesy wwiiaircraftperformance.com)
As evidenced by the chart the manifold pressure or “boost” level fluctuates between +18 lbs/sq in to 0 lbs/sq in as altitude and supercharger gearing changes.”
If you can do this with charts, even better. People love charts even if they have no clue what the chart means. It helps to add to your level of credibility and authority! But supporting the principle behind your hypothesis still isn’t enough though. We haven’t sealed the deal yet. After all supporting your principle only gives us an idea that perhaps you know what you might be talking about but it doesn’t do a lick to prove anything yet.
STEP 3: TEST YOUR HYPOTHESIS TO PROVE (OR DISPROVE) IT
This is where the rubber meets the road when it comes to FM zingers! Infact people realize this as much that they rush off from STEP 1 to STEP 3 and totally leave out STEP 2. Don’t make this mistake. STEP 2 is important because it gives you a basis for the principle that you will be testing against in STEP 3. ½ of ½ of all FM zingers with clearly stated hypothesis fall for this trap. Assuming that it hasn’t and that we’re in the 10% that haven’t skipped STEP 2, we’re now ready to do the testing and to demonstrate the hypothesis.
In your manifold pressure case, we’ll be generous and give you a C- for it. It’s hard to tell what kind of testing you’ve done and you make some statements in the affirmative as if you or someone else did but clearly HiTech thinks you haven’t. Why is that? Well you’ve not presented the data of your tests of course! But the trick here is NOT ONLY PRESENTING YOUR DATA, the trick is to do this COMPARED AGAINST YOUR PRINCIPLE IN STEP 2. See a lot people will throw out data in a form of test but not against any principle. And when they do we don't have an inkling of the cause and effect relationship they are trying demonstrate.
Here’s how you could have done this much much better, in fact without even actually flight testing it!
TEST: We’ll examine the Aces High Rate of Climb to see if it demonstrates the similar pattern found like in the actual flight test report listed above. Let’s examine the Spitfire Mk XVI in Aces High. I could have chosen the AH Spitfire Mk VIII to match the figures above but since you were talking about the Spitfire XVI we’ll just do that for the heck of it (Nevermind that the Mk VIII uses the Merlin 66 which is what our Mk XVI uses because it’s really just a Mk IX LF with a Merlin 66. Why are the Brits so confusing anyway???? Centre vs. center, colour vs. color?? Really.). Here’s the published RoC chart compared between a Spitfire Mk IX and Spitfire Mk XVI (WEP Power):
(http://thetongsweb.net/images/roc.png)
Well crap. Sure is funny that the AH rate of climb chart exhibits the similar raggedy lines that the real flight test RoC chart shows, especially as altitude increases RoC decreases. What does this all mean??? Well one possibility is that the AH Spitfires engine power output (and thus manifold pressure) actually does decrease with altitude. Huh, fancy that.
But we all know that AH can’t be 100% right right??? So there must be other possibilities of why the AH FM is screwed up and wrong and the manifold pressure goofed! We just have to go fish for some more data to prove our point or repeat steps 1-3 as necessary until we do!
So there you go, 3 E-Z steps to positively make your FM zinger stand out from the rest of the rabble! I’ll let you go figure out how you can apply this to your “drag” question!
Peace, Out!
Tango
412th FS Braunco Mustangs
Well Im Sorry but all through my life i have had to deal with certain learning difficulty's that have kept me from properly putting my point across. The truth be told i am lucky to have managed to become an airframes engineer. With the Royal Air Force and to have worked on some of the best and most challenging aircraft. Hell I'm 1 of 40 Technician's that will be sent to the US to train on maintenance for the YF32 VTOL fighter. Now With my learning and pronunciation difficulty's **** all who take the mick of me. But If you research some of what i have said about the Spitfire Mk16 you will find im more or less right on the subject. So to all those who have taken the mickey **** OFF as we the ones that have a clue would like to have this discussion as an aid to the team at HiTech to help improve the game. and also i have spastics on paper work from the old aeroplane magazine collection to show these types of aircraft performance's.
As For you dtango Thankyou for your post <S>
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Bullet wrote:
I'll get right on that and add drag to the sim. How could I have forgotten such a basic concept.
As for your manifold press posting.
Do some real testing, you will find out the manifold pressure starts to drop at their critical alts on all planes .
HiTech
you may have or not you may even have kept all aircraft producing the same amount of drag when they all produce different drag amounts. As for the manifold pressure it doe's drop as all aircraft get higher and can be controlled by throttle mixture to a certain point when the pilot has to apply emergency turbo boost ( i.e War Emergency Power ) at high alts to keep above stalling speed. You see Wep Is not a button or switch you press its in the throttle control. It was the forefather to the Afterburner ( reheat ) on todays jet fighters.
Thankyou HiTech
Why dont you read up on the physics of flight a bit.
And i may get banned from the forums or the game for this but go back to college
:mad: :mad: :mad: :t :t :t :t :t
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all i can say is what :huh :huh
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On my 19th Post i meat statistic's i do appolagize <S>
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Wow BulletVI, do you REALLY think hitech could forget that a bomber has more drag than a fighter? And that a 110 will have more drag than a 109?
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WOW :headscratch:
BulletVI: I very sincerely suggest you stop commenting on how things work and start asking how things work. You last post has crossed the thresh hold an started to almost become insulting.
Because in this statement.
you may have or not you may even have kept all aircraft producing the same amount of drag when they all produce different drag amounts. As for the manifold pressure it doe's drop as all aircraft get higher and can be controlled by throttle mixture to a certain point when the pilot has to apply emergency turbo boost ( i.e War Emergency Power ) at high alts to keep above stalling speed. You see Wep Is not a button or switch you press its in the throttle control. It was the forefather to the Afterburner ( reheat ) on todays jet fighters.
I count at least 6 major inaccuracies that show your lack of knowledge on the subject matter. In fact every sentence in the paragraph is inaccurate.
To everyone else, please do not light the flame throwers until his next response. Fish in a barrel are hardly considered sport.
HiTech
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Lol HT, OK sir. But I've got the matches ready.
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(http://www.funnyforumpics.com/forums/flame-insults/1/Belittle-Flame_Thrower.jpg) (http://"http://www.funnyforumpics.com")
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Must resist urge....
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:huh
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You see Wep Is not a button or switch you press its in the throttle control.
Sorry couldn't resist....
How do you propose HT simulate pushing past the wire stop that was used in ww2? I for example have a lowly x-52 throttle and do not have a detent for wep/afterburner.
Airframes engineer or air frame mech/tech? Huge diff IMO.
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YYYYYYYYYYYYYYAAAAAAAAAAAAAAA AAAAAAAAAWWWWWWWWWWWWWWWWWWWW NNNNNNNNNNNNNNNNNNNNNNNNNNN
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Ok this one is dead.
HiTech