Aces High Bulletin Board
Help and Support Forums => Help and Training => Topic started by: Oldman731 on December 15, 2008, 08:41:47 AM
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Not that I've got any place telling people how to fly, but I thought I'd mention this anyway.
It seems to me that the vast majority of people I fly against, in all arenas, enter the engagement at full throttle and keep it there until their WEP runs out. There are some planes - P-40B comes to mind - where you probably have no choice. But there are not many such planes (fighters, at least). So it might pay some of you to try pulling the throttle back some (not necessarily all the way) when you're turning, or at the top of a loop, especially if you're flying one of those aircraft with good energy qualities (think Spitfire). Makes a really big difference.
- oldman
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Not that I've got any place telling people how to fly, but I thought I'd mention this anyway.
It seems to me that the vast majority of people I fly against, in all arenas, enter the engagement at full throttle and keep it there until their WEP runs out. There are some planes - P-40B comes to mind - where you probably have no choice. But there are not many such planes (fighters, at least). So it might pay some of you to try pulling the throttle back some (not necessarily all the way) when you're turning, or at the top of a loop, especially if you're flying one of those aircraft with good energy qualities (think Spitfire). Makes a really big difference.
- oldman
chopping throttle at the top of a loop in the 38 works especially well. :D
BTW......it is always appreciated when you guys come in, and offer up this advice!! that "which way do i turn" thread is awsome!
thanks!
<<S>>
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I as well am no authority, but I've taken to looking at the E6b to see what the "normal" throttle setting is. After takeoff and climbout, I set the throttle to "normal" setting, and leave it there until I think I need to go to max during a fight. Then go back to normal - I fly 90-95% of my sortie at normal power - you'd be amazed at how much longer you can stay flying if you don't keep the throttle firewalled.
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I climb up to whatever altitude im cruising at for the day with full throttle, sometimes WEP if I want to burn off some of my initial fuel loadout. Once there it's normal or maximum cruise until I'm about to get into combat. I try to go full throttle well before I see any enemies so that I can get my maximum speed up without diving by the time I do see them.
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The only time I chop throttle is when I am either avoiding or forcing a flight path overshoot.
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I'll be the one to ask the dumb questions...
So I understood that if you were above corner speed, that speed simply increases your turn radius (because you can't pull anymore Gs than blackout will allow). So reducing throttle there makes sense.
What is the advantage of closing throttle below corner speed?
Also, what are the advantages of reducing rather than completely closing throttle when you might want to decelerate? (Advantages in sim I mean, not r/l concerns with taking care of the engine or spool-up times.)
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I'll be the one to ask the dumb questions...
So I understood that if you were above corner speed, that speed simply increases your turn radius (because you can't pull anymore Gs than blackout will allow). So reducing throttle there makes sense.
What is the advantage of closing throttle below corner speed?i could be wrong, but......assume, you're in a 38, doing 200, and turning hard. throttles firewalled, you've got those two allisons tring to pull your airplane straight. in the meantime, you're pulling elevator, trying to bring her 'round. so you're kinda fighting yourself. lower throttles a little, and now, you're providing enough thrust to keep going, but not fighting your control inputs as badly.
Also, what are the advantages of reducing rather than completely closing throttle when you might want to decelerate? (Advantages in sim I mean, not r/l concerns with taking care of the engine or spool-up times.)
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I'll be the one to ask the dumb questions...
So I understood that if you were above corner speed, that speed simply increases your turn radius (because you can't pull anymore Gs than blackout will allow). So reducing throttle there makes sense.
What is the advantage of closing throttle below corner speed?
I'll leave engineering questions to the engineers. From a practical standpoint, during a turn fight it is unwise to stare at your airspeed indicator, so your ability to maintain corner speed for more than a second or so is quite limited. Your turn radius at less than corner speed will still be shorter than your turn radius above corner speed. Reducing throttle helps ensure this. (Also: Is corner speed necessarily the best turn radius, or is it the best combination of turn radius and turn rate? Seems to me that your best turn radius will almost always be at the slowest forward speed.)
Also, what are the advantages of reducing rather than completely closing throttle when you might want to decelerate? (Advantages in sim I mean, not r/l concerns with taking care of the engine or spool-up times.)
If, for example, you're trying to get good angles on a bandit in a turn, you will often be able to cut inside his turn by reducing your throttle. If you close it completely, though, your closure rate will also decrease; so you pull the throttle back enough to observe an adequate increase in your turn radius, but not so much that you lose distance.
Also, at the top of a loop or in a very tight turn fight, closing your throttle all the way might result in a stall. Closing it just a bit will work the turn magic without the stall.
- oldman
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I'll be the one to ask the dumb questions...
So I understood that if you were above corner speed, that speed simply increases your turn radius (because you can't pull anymore Gs than blackout will allow). So reducing throttle there makes sense.
What is the advantage of closing throttle below corner speed?
Also, what are the advantages of reducing rather than completely closing throttle when you might want to decelerate? (Advantages in sim I mean, not r/l concerns with taking care of the engine or spool-up times.)
109'S (the K-4 in particular) benefit a lot from chopping throttle due to torque. I can't comment on many other planes outside of the German set, but it is probably the same.
Next time you take a K-4 up, throttle up for a left turn, then chop throttle and kick a little right rudder for a right turn. Someone just brought this to my attention and it made a heap of difference.
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What is the advantage of closing throttle below corner speed?
Also, what are the advantages of reducing rather than completely closing throttle when you might want to decelerate? (Advantages in sim I mean, not r/l concerns with taking care of the engine or spool-up times.)
There's a multitude of answers to this that might not have anything to do with corner speed. Backing off to remain behind someone in a scissor, backing off to force an overshoot, backing off to avoid an overshoot, etc.
A lot of times in the midst of a fight I'll reduce throttle for an extended period. One because my hands and mind are busy with other things but also because it helps manouverability. It also disguises my gradual loss of E (speed) which seems to allow for some pretty nifty inside turns and snapshots. I'll reach down and throttle back up if/when I need to but for several turns I won't even worry about it.
I find this particularily helpful in Spits due to their great ability to retain E in a turn and in the K4 due to it's excessive engine strength. I've fought entire fights in the K4 at 40-60% throttle and it's pretty nimble at that setting.
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THe K-4 is a monster and I am learning quickly that it can be harnessed. Most of comes through throttle management. Due to the excessive engine strength mentioned, it is most noticeable in that particular plane. Like night and day.
I have a squaddie that has been drilling into me that throttle management can make or break most fights.
And he is right :aok
It's like flying a totally different plane-set, now.
;)
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What is the advantage of closing throttle below corner speed?
Also, what are the advantages of reducing rather than completely closing throttle when you might want to decelerate? (Advantages in sim I mean, not r/l concerns with taking care of the engine or spool-up times.)
Oldman's reply is incorrect. Turn rate and radius gets worse the more below corner you go. This applies in the vertical as well. This is not why you chop throttle at or below corner.
Baldeagl's reply is on the mark. If you're reducing throttle below corner it isn't for improving turn performance but for other things. For instance in the "Which Way Do I Turn?" thread in my last post I point out a situation in a nose to nose turn when turn radius isn't the deciding but rather the slower relative forward speed. You have to recognize when that's the case versus not.
Reducing throttle partially vs. all the way reduces the amount of prop drag you would have. I can't think of an advantage unless you wanted to not bleed as much speed compared to bringing throttle to idle.
Tango, XO
412th FS Braunco Mustangs
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Throttle control is a hard thing to master, when it comes to 1v1 fighting. It can, for certin, change the direction of a fight very quickly, if your not payin attention. If you reduce throttle, of course is going to give you more manuverability, it can hurt you when your doing more of a vertical E fight, rather than a dog fight, but the benifits are better than the risks. I personally, use it all the time to beat some hard people in planes that are better than me. In a G6, I know for a fact with throttle control, you can out turn spixteens just on that.
It just takes a lot of time and practice to do it right, you have to know when and were you need to back off on the throttle in a 1v1 fight.
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There are a few ways to describe throttle control in a corner, lets start in grade school. When ridding your bike as fast as you could would you decelerate for a corner...Why?
Now your older and driving a car. As you approach a curve set for 30 miles an hour could you do 70? The limits for that curve might be 50+ with an average car and a good suspension. Why? Tires are actually part of the suspension in case you did not know.
Answer to both questions is centrifugal force.
Unlike a car or bike, the only real friction you have to consider is the air itself while flying a plane.
The plane is being pulled through the air by a propeller powered by an engine and is stationary. The propeller pulls in a straight line best. As in the exemplary explanations in the posts above, your plane has to fight the engine.... or propeller(s) pulling force, while in a turn.
To turn tighter you'll need to relieve most of the force that wants to pull you forward and use the friction of the wind hitting your rudder to slow you down further, which at times can help you swing the rear of the plane out sending you in a different direction allowing full throttle to be maximized once straight again.
This Film was made for the Aces and not the masses. It explains to a minor extent how important throttle control is when in a dogfight and how to use it to your advantage when trying to line up or position yourself for a kill. It has a few interruptions and made spur of the moment. You'll see 4 or five Throttle Management Kills.
http://www.mediafire.com/download.php?dnmjynnbh3t
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Where to start? :)
Going slower than corner your turn performance absolutely and positively gets worse. Why some folks think chopping throttle below corner improves your maneuverability is beyond me. I don't know where people get the idea that the slower you go the better turning you are. I think it comes from using the inaccurate car/bike analogy. That's a bad analogy to use.
Here's something I posted awhile back that I hope helps:
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I think we need to clarify the relationship between airspeed and turn-radius. Here are some excerpts from something I posted awhile back.
Corner velocity is where an aircraft's maximum turn-rate, and minimum turn-radius occurs for a fixed aircraft configuration (e.g. no flaps etc.). Have a look at one of Badboy's past Energy-Maneuverability diagrams:
(http://www.badz.pwp.blueyonder.co.uk/images/Corner.jpg)
Here's an EM chart of the Spit MkI, Hurricane MkI, and Bf-109E. Notice the turn-radii for the aircraft. Turn-radius never gets smaller than the turn-radius at corner speed. Infact turn-radius actually increases the slower you get below corner speed. So what gives? Simply put, in a level turn below corner speed an airplane cannot generate as much lift as is possible at higher speeds up to corner, thus it can't turn as sharply. The reason is turn-radius is also a function of the maximum g-loading / turning-bank-angle that the aircraft can attain. Here is the level turn-radius equation:
(http://brauncomustangs.org/images/eq08-m2.gif)
Eventhough a lower airspeed reduces the numerator, the denominator also reduces with airspeed. Maximum turn load-factor "n" (g-load) and maximum turn bank-angle "theta" vary in direct proportion to airspeed. The lower the airspeed below corner, the lower the max g-load / bank angle an airplane can achieve.
Why is this? Because the slower we go below corner speed, the less lift we are able to achieve and thus the less we're able to turn.
In a level turn we need "vertical" lift to not only support the weight of the aircraft, but we also need additional lift in the "horizontal" direction to create angular acceleration to curve our flight path. Thus to turn we need to create more lift than weight of the airplane and incline the airplane at a bank angle to take advantage of the additional lift to turn the plane. The tighter the level turn, the more lift is needed in the horizontal direction as depicted below:
(http://www.dfrc.nasa.gov/Education/OnlineEd/Intro2Flight/Images/Wut/WUT7lit.JPG)
(http://www.dfrc.nasa.gov/Education/OnlineEd/Intro2Flight/Images/Wut/WUT8lit.JPG)
Remember that lift is directly proportional to lift coefficient (Cl) and airspeed squared. To increase lift we can either increase Cl by increasing angle-of-attack (elevator input), increase airspeed, or both. In a max performance turn, we can easily attain maximum lift coefficient by yanking back on the stick regardless of airspeed. If Cl is fixed at it's maximum through elevator input the only other variable that varies is airspeed. So if you're at Clmax and low airspeed, this is lower lift than obtainable compared to Clmax at a higher airspeed. Lower airspeed => lower lift => less capability to turn.
So how do we explain the charts from Dok Gonzo's website where turn radius is lower for lower airpseed? It all has to do with high-lift devices like flaps and slots. Remember that we can increase lift by increasing lift coefficient. High lift devices like flaps increase the maximum lift coefficient of an aircraft. This means this increases the amount of lift capable and also reduces the airspeed to create equivalent lift in a turn compared to the same aircraft without the high-lift device deployed. Here's another EM Chart from Badboy to demonstrate.
(http://www.badz.pwp.blueyonder.co.uk/images/P-38flaps.jpg)
Notice the P-38 with no flaps vs. with 5 notches of flaps. The flaps enable the P-38 to decrease it's turn-radius from 800 ft (@260mph) down to below 600 ft (@195mph). This is because the flaps allow the aircraft to obtain a higher maximum lift coefficient. With flaps this enables the aircraft to obtain the equivalent lift with no flaps but at a much lower airspeed. Notice however that with 5 notches of flaps that the turn-radius increases (turn performance is getting worse as we now expect) the lower below "corner speed" the airplane goes.
I hope that helps to enlighten the topic.
Tango, XO
412th FS Braunco Mustangs
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Where does chopping throttle make sense from an angles perspective? Here's one specific instance I posted in another thread worth repeating....
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Impact of Airspeed on Nose-to-Nose Turns
Separation distances between aircraft impacts nose-to-nose engagements in other ways as well. Turn radius is actually not the only factor that determines advantage in one-circle engagements.
In certain nose-to-nose situations turn radius doesn’t determine angular and positional advantage. Instead it’s determined by airspeed instead. How much advantage depends on the separation distances between airplanes. Consider the following diagram:
(http://thetongsweb.net/images/one_circle_sep2.jpg)
In the illustration we have red and blue abeam of each other with circular flight path overlays to visualize the turn circles. Red has a smaller turn radius but greater airspeed while Blue has a larger turn radius but is travelling slower than Red. Blue is able to get the angles advantage because it is travelling slower than Red despite it’s larger turn radius and lower turn rate!
In a nose-to-nose turn when aircraft are abeam of each other and the separation distance between the two is less than the turn radius of the larger turn circle the aircraft with the slower airspeed gains the advantage.
This is one of the ways planes like the P-51 will catch better turners by surprise. For instance when I’m flying a P-51 against a Spitfire XVI and I recognize that we’re in this situation I’ll yank throttle to idle and deploy as much flaps as I can in an effort to slow down and force the Spitfire out front. This is a situation where chopping throttle makes sense. Just keep in mind that it may leave you no margin for error if you can't get in position to make that shot count with your throttle chopped.
If the separation is greater than the larger of the two turn radii then turn radius becomes the dominant factor once again.
Tango, XO
412th FS Braunco Mustangs
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Thanks dtango, you've saved me quite a bit of typing time.
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Thanks dtango, you've saved me quite a bit of typing time.
Hehe murdr. I'd say you owe me :D!!! .... except for the fact that I was pretty much cutting and pasting from past posts anyway! :rock
Tango, XO
412th FS Braunco Mustangs
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Why some folks think chopping throttle below corner improves your maneuverability is beyond me. I don't know where people get the idea that the slower you go the better turning you are. I think it comes from using the inaccurate car/bike analogy. That's a bad analogy to use.
For some of us it comes from experience.
Your chart shows why. There's no question that your instantaneous turn radius and rate are best at corner velocity; you've convinced me. But corner velocity only exists in a fight for a brief moment, unless you're literally staring at your airspeed indicator throughout the it's-gonna-be-quick-now fight. People slow down because it gets them closer to the best sustained turn rate, which is what usually counts when you're pursuing someone, and even after you've made your original break turn.
- oldman
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For some of us it comes from experience.
Your chart shows why. There's no question that your instantaneous turn radius and rate are best at corner velocity; you've convinced me. But corner velocity only exists in a fight for a brief moment, unless you're literally staring at your airspeed indicator throughout the it's-gonna-be-quick-now fight. People slow down because it gets them closer to the best sustained turn rate, which is what usually counts when you're pursuing someone, and even after you've made your original break turn.
- oldman
OK let's talk about this idea of slowing down to best sustained turn. Why would you not turn from corner and bleed down to best sustained turn with throttle on? Your radius would probably be smaller and turn rate greater compared to simply chopping throttle while doing this. With throttle on you would have more specific-excess-power available to counter increased drag due to lift which means you can turn tighter and at the same or smaller radius compared to with throttle off.
There are times when chopping throttle makes sense (e.g. trying to induce overshoots etc). Saying that chopping throttle makes you more maneuverable as a general maxim is very misleading because it doesn't apply in many cases.
Tango, XO
412th FS Braunco Mustangs
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Slowing down in a turn that you already know you are going to fast to make tighter to take the shot is the way to go. Most high speed turns can only be made tighter by either reducing engine power or increasing engine tork, I don't think anyone can convince me otherwise.
I realize some planes turn better to left and others to the right. Some planes turn better slow and others just need more speed to stay aloft and competitive. Retaining information like that has helped me determine when to throttle down and when to wep up. It's especially useful when considering engine tork and always depends on the choice of plane.
It's an ongoing process of trial and error for me and it does not always work out like I want it. The charts say one thing but applying them effectively in the heat of battle is harder to do than just using my best judgment. Since I've never fully divided my attention between the gauges and the fight I probably won't ever become the greatest sim fighter pilot ever.... but I have gained some experience and do have a lot of fun :)
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It's not about chopping throttle, It's about throttle management, flaps and rudder. When to use them and why.
With the exception of planes like the pony and the f4u's, there are many planes that won't deploy flaps at higher speeds . In these planes throttle management is key. Learning which ones to do what in is challenging when you don't dedicate yourself to one type or another but all of them.
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OK let's talk about this idea of slowing down to best sustained turn. Why would you not turn from corner and bleed down to best sustained turn with throttle on? Your radius would probably be smaller and turn rate greater compared to simply chopping throttle while doing this. With throttle on you would have more specific-excess-power available to counter increased drag due to lift which means you can turn tighter and at the same or smaller radius compared to with throttle off.
There are times when chopping throttle makes sense (e.g. trying to induce overshoots etc). Saying that chopping throttle makes you more maneuverable as a general maxim is very misleading because it doesn't apply in many cases.
Because of two things. First, you aren't necessarily "chopping" the throttle, as A8Tool points out. You would chop it if you were in danger of overshooting or were going way too fast, but generally I'm talking about reducing the throttle by something less than 100%.
Second, it's really the difference between theoretical and practical. Theoretically it might be best to slow down exactly along the chart's curved line, but practically it's not possible to do this because you aren't sure what speed you began at and you aren't watching the airspeed indicator (unless you plan to lose sight of your target or of your pursuer). I guess this was my original thought in starting this thread - many of the people I see aren't adjusting their throttle at all, probably because they know they can't watch their airspeed indicator and they're worried about getting too slow. Slowing down enough to see that your turn is improving - regardless of whether you happen to be moving along the perfect-speed-line - is often a very useful technique.
- oldman
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There's no question that your instantaneous turn radius and rate are best at corner velocity; you've convinced me. But corner velocity only exists in a fight for a brief moment, unless you're literally staring at your airspeed indicator throughout the it's-gonna-be-quick-now fight.
Not true. If you are used to a specific aircraft you can hold it at corner velocity for extended periods without ever looking at your airspeed indicator. Beyond that, you have visual clues in a fight; am I gaining or losing ground and how quicky? Minor adjustments of turn radius or throttle provide nearly instantaneous feedback as to the result; am I gaining/losing faster or slower than before or has the situation reversed itself? Note that in these scenarios not once would you be looking at the instrument panal, yet you're maximizing your aircraft at it's best sustained turn rate.
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Because of two things. First, you aren't necessarily "chopping" the throttle, as A8Tool points out. You would chop it if you were in danger of overshooting or were going way too fast, but generally I'm talking about reducing the throttle by something less than 100%.
Second, it's really the difference between theoretical and practical. Theoretically it might be best to slow down exactly along the chart's curved line, but practically it's not possible to do this because you aren't sure what speed you began at and you aren't watching the airspeed indicator (unless you plan to lose sight of your target or of your pursuer). I guess this was my original thought in starting this thread - many of the people I see aren't adjusting their throttle at all, probably because they know they can't watch their airspeed indicator and they're worried about getting too slow. Slowing down enough to see that your turn is improving - regardless of whether you happen to be moving along the perfect-speed-line - is often a very useful technique.
- oldman
First, I'm absolutely in agreement with BaldEagl's response. You don't need to be staring or constantly glancing at your airspeed indicator. There are visual cues. Personally before any kind of merge I note where my airspeed is at and make decisions and adjustments from that "initial" condition during a fight.
2nd - there is no "theoretical" here. If you're turning better when you slow down assumming no incremental employment of high lift devices then either you a) started the turn above corner or b) were not in a max performance turn already before you got slower.
I'm in violent agreement that "two-handed-turns": one on stick, one on throttle is a skill to learn. Learning the abilities of your aircraft, the envelope to fly it in, and the visual cues from the airspeed indicator to watching the movement of your opponent relative to you and modulating your throttle and stick as appropriate to maximize your performance is paramount.
My point is when you're in this mode, to improve turn performance sometimes you want to throttle it back, sometimes you want to throttle it up, sometimes you do both within a matter of a few seconds. To say that throttling back ALWAYS improves your turn performance is a fallacy though.
Tango, XO
412th FS Braunco Mustangs
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If you're turning better when you slow down assumming no incremental employment of high lift devices then either you a) started the turn above corner or b) were not in a max performance turn already before you got slower.
My exact point. It's fine if you're able to note your airspeed at the beginning of a fight, but quite often - most often, for me at least - you aren't. More, you may not have flown the plane in awhile, and you perhaps don't know the corner speed or the sustained turn speed in any case.
I'm in violent agreement that "two-handed-turns": one on stick, one on throttle is a skill to learn. Learning the abilities of your aircraft, the envelope to fly it in, and the visual cues from the airspeed indicator to watching the movement of your opponent relative to you and modulating your throttle and stick as appropriate to maximize your performance is paramount.
My point is when you're in this mode, to improve turn performance sometimes you want to throttle it back, sometimes you want to throttle it up, sometimes you do both within a matter of a few seconds. To say that throttling back ALWAYS improves your turn performance is a fallacy though.
Then we agree.
- oldman
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My exact point. It's fine if you're able to note your airspeed at the beginning of a fight, but quite often - most often, for me at least - you aren't. More, you may not have flown the plane in awhile, and you perhaps don't know the corner speed or the sustained turn speed in any case.
As long as you have a ballpark idea of your speed that's all one needs.
1. Can I induce a full visual black out? Yes=at or above Cv No=see #2
2. Can I induce a 1/2 visual black out? Yes=between Cv and Sustained No=see #3
3. Can I deploy flaps? Yes=see #4 No=near or below sustained but above flap speed.
4. Can I induce near a full black out? Yes=near max flap speed (flap Cv). No=see #5
5. Can I induce a 1/2 visual black out? Yes=between Cv and Sustained
For throttle management considering ONLY max turn performance: 4 in a nose down attitude I would consider chopping the throttle. 1 I would consder chopping the throttle if it was in a nose down attitude, or if I felt "too far" above Cv. 3 I might consider slowing to flap speed by chopping the throttle if it's appropriate. It's possible I'm forgetting a scenario, but that's pretty much it for reducing throttle to achieve the best turn performance.
The point is that other reasons for reducing power are not "to turn tighter"/max performance. The reasons are about relative E states, or the geometry of the fight, or reducing the dominante torque force at or below stall.
Sustained turn is simply where your power output and the forces consuming that power are at equalibrium. Reducing power at that part of the envelope only makes your turn performance worse.
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I could be wrong but it seems to me that the best sustained turn rate in most planes happens just as the stall horn starts to sound and just before you enter the stall buffet.
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What is the advantage of closing throttle below corner speed?
There are many times when I will chop throttle (full chop) to assist in a tight ruddering move to snap the plane around much quicker ... for a snap shot or to gain an advantage behind one's 3-9 line on a merge.
I mainly fly the FM2 and F5F and throttle control is paramount in those planes when trying to tussle with Spit and Hurricanes. Many people cannot understand how these planes can get around so quickly either in a turn or rolling scissors.