Aces High Bulletin Board
Help and Support Forums => Help and Training => Topic started by: Traveler on February 18, 2010, 10:00:21 AM
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I've attempted to fly several aircraft according to the Pilots flight manuals of the era. Why is it that all the aircraft seem to fly off the deck at around 100 MPH. That just shouldn't be so.
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Only US Army aircraft used MPH, so are you converting from knots in the manuals correctly? Are you considering the weight and historical take-off configurations?
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Military Power/Normal Power perhaps?
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Traveler could you be more specific? Which aircraft, loadout, listed stall speed, suggested takeoff speed, vs in game performance?
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No wind to help out maybe?
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Only US Army aircraft used MPH, so are you converting from knots in the manuals correctly? Are you considering the weight and historical take-off configurations?
Yes, I am a certified flight instructor. I converted the 65Knots for the F6F to75 MPH 65 X 1.15 is just a shade under 75 MPH.
It won't fly at 75. That's just not right. That with 25% fuel only.
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Traveler could you be more specific? Which aircraft, loadout, listed stall speed, suggested takeoff speed, vs in game performance?
F6F, 25% fuel only. nothing else. book says 65Knots, that's should be 75MPH.
http://www.youtube.com/watch?v=hQ55LmRwkQg
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Traveler could you be more specific? Which aircraft, loadout, listed stall speed, suggested takeoff speed, vs in game performance?
F6F Hellcat, 25% fuel, nothing else. should fly at 75MPH, 65Knots,
watch this http://www.youtube.com/watch?v=hQ55LmRwkQg
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(http://i.ehow.com/images/GlobalPhoto/Articles/5099299/2843172791a8ec502709o-main_Full.jpg)
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Your question is valid, Traveler, based on the handbook. Many sources (including the pilot handbook) are not clear or consistent with aircraft configuration, weight and also whether the speeds listed are indicated, calibrated or true. Ironically, the F6F handbook is famously unclear and inconsistent about stall speeds.
Here is an original test report indicating 86.5 MPH for the F6F-5 on page 11: Link>> (http://docs.google.com/viewer?a=v&q=cache:TpkfAbiDjvEJ:www.wwiiaircraftperformance.org/f6f/f6f-5-58310.pdf+F6F-5+performance+charts&hl=en&pid=bl&srcid=ADGEESgUIRK4I8ZBBXTNz-2T8ohpPA0EUnGMVUYpCBk7Dmdpg9jMusTyVTVy1GVvGUiDJR06dbNsAiJTjfiosaupzh7Hfwy6O3DwEN40jgqL6j17PKKqoWuQgY0d37DP4Y1fFU2YFGQf&sig=AHIEtbRZEMtp9sVa5j6MrYYhZQCvdsb3tQ)
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Interesting. Power on stall speed with 25% fuel and no ammo, A/C weight 11000 lbs, My F6F-5 POH pdf lists 65 Knots IAS. My AH minimum take off speed is 73 Knots, 84 MPH at 11000 lbs. My POH pdf also has 2 conversion charts for IAS speeds listed without context. One chart says add 12 Knots at 100 Knots, the other says subtract 5 Knots at 100 Knots. Call it 8 and 3 and we get 73 and 62. I don't know if the listed speed includes the correction or which correction is correct.
Traveler does your POH list an IAS correction chart?
Edit: Power at 53".
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Interesting. Power on stall speed with 25% fuel and no ammo, A/C weight 11000 lbs, My F6F-5 POH pdf lists 65 Knots IAS. My AH minimum take off speed is 73 Knots, 84 MPH at 11000 lbs. My POH pdf also has 2 conversion charts for IAS speeds listed without context. One chart says add 12 Knots at 100 Knots, the other says subtract 5 Knots at 100 Knots. Call it 8 and 3 and we get 73 and 62. I don't know if the listed speed includes the correction or which correction is correct.
Traveler does your POH list an IAS correction chart?
Edit: Power at 53".
The only chart I have are for indicated airspeeds corrected to true for Altitude and temperature.
did you watch this training film? http://www.youtube.com/watch?v=hQ55LmRwkQg
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The pitot tube location on the F6F required a correction chart for IAS because the gauge didn't read IAS accurately. I believe it was a placard inside the cockpit. This was not a correction to TAS. The IAS corrections for flaps up and flaps down were also different.
I've seen the video but I don't consider "about 60 knots" in a training film to be more than ballpark. It also doesn't address my question regarding actual corrected IAS vs IAS shown on the gauge.
AH roughly matches the speed listed on Rolex's link but I didn't test the weight used at the link. Also, I was watching just the main gear so my speed could be slightly low.
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The pitot tube location on the F6F required a correction chart for IAS because the gauge didn't read IAS accurately. I believe it was a placard inside the cockpit. This was not a correction to TAS. The IAS corrections for flaps up and flaps down were also different.
I've seen the video but I don't consider "about 60 knots" in a training film to be more than ballpark. It also doesn't address my question regarding actual corrected IAS vs IAS shown on the gauge.
AH roughly matches the speed listed on Rolex's link but I didn't test the weight used at the link. Also, I was watching just the main gear so my speed could be slightly low.
About 60 Knots translats to about 70 MPH but I noticed that the F6F I flew with 25% fuel was about 100 MPH to get off the gound. that's a major difference to me.
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I don't know why you need 100 MPH and I only needed 84. That's a big difference too. You seem to have missed every relevant point I posted in this thread as well as Rolex's link.
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I don't know why you need 100 MPH and I only needed 84. That's a big difference too. You seem to have missed every relevant point I posted in this thread as well as Rolex's link.
One possible explaination was I did not use flaps. however the pilots operations manual states that off of land based runways no flaps would be required. The F6F in the film flys off at 60 knot with the flaps up. I can fly off the runway at 75 MPH if I use full flaps.
Would be interesting to know what the source of the performance information was that HiTech Creations used and if that's available online anywhere.
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I just checked. I got to around 80-90 mph for takeoff at 25% fuel no flaps. Note I am at the edge of stall while pulling up for these.
Auto-takeoff puts the Hellcat around 110 mph.
Nothing seems terribly wrong (i.e., everything you've mentioned seems to be within measurement error).
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I should have noted that I didn't use flaps.
Boomerlu because of the acceleration it's easier to see the speed your wheels lose contact if you use film.
The POH gives a 65 Knot power on stall speed in landing configuration for 11000 lbs. 11000 lbs is 25% fuel and no ammo. Wouldn't landing configuration include flaps? The video states you can take off at about 60 Knots. :headscratch:
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I should have noted that I didn't use flaps.
Boomerlu because of the acceleration it's easier to see the speed your wheels lose contact if you use film.
The POH gives a 65 Knot power on stall speed in landing configuration for 11000 lbs. 11000 lbs is 25% fuel and no ammo. Wouldn't landing configuration include flaps? The video states you can take off at about 60 Knots. :headscratch:
maybe in wind? with no wind in AH it might not help with lift?
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Wind isn't an issue here. Note that the stall speed is 5 Knots higher than the takeoff speed stated in the film. That probably matched the empty weight stall speed, i.e. no fuel, and might be sloppy editing of the film script, or it just might be the uncorrected IAS, as I noted earlier in this thread.
Taking off in a headwind or tailwind affects your ground speed, not your indicated air speed. IAS is a pressure measurement. That's why it's location affects it's accuracy and the correction for accurate IAS is different in the F6F for flaps up vs flaps down.
In AH the IAS on the gauge is the actual IAS but in the real F6F the IAS on the gauge had to be corrected for different speeds and flap configurations. Then the corrected IAS had to be converted to TAS, true air speed, and you had to allow for wind, in order to navigate over the ocean and find your carrier again.
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Wind isn't an issue here. Note that the stall speed is 5 Knots higher than the takeoff speed stated in the film. That probably matched the empty weight stall speed, i.e. no fuel, and might be sloppy editing of the film script, or it just might be the uncorrected IAS, as I noted earlier in this thread.
Taking off in a headwind or tailwind affects your ground speed, not your indicated air speed. IAS is a pressure measurement. That's why it's location affects it's accuracy and the correction for accurate IAS is different in the F6F for flaps up vs flaps down.
In AH the IAS on the gauge is the actual IAS but in the real F6F the IAS on the gauge had to be corrected for different speeds and flap configurations. Then the corrected IAS had to be converted to TAS, true air speed, and you had to allow for wind, in order to navigate over the ocean and find your carrier again.
I see, thank you for the clear explanation.
Did they ever fix the incorrect IAS gauge? or just leave it as it was and continue with the adjustment cards?
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Wind isn't an issue here. Note that the stall speed is 5 Knots higher than the takeoff speed stated in the film. That probably matched the empty weight stall speed, i.e. no fuel, and might be sloppy editing of the film script, or it just might be the uncorrected IAS, as I noted earlier in this thread.
Taking off in a headwind or tailwind affects your ground speed, not your indicated air speed. IAS is a pressure measurement. That's why it's location affects it's accuracy and the correction for accurate IAS is different in the F6F for flaps up vs flaps down.
In AH the IAS on the gauge is the actual IAS but in the real F6F the IAS on the gauge had to be corrected for different speeds and flap configurations. Then the corrected IAS had to be converted to TAS, true air speed, and you had to allow for wind, in order to navigate over the ocean and find your carrier again.
If you review the document at the link given by Rolex it describes the flight test in great detail. The F6F was tested at the aircraft gross weight of 12410 lbs that full fuel of 250 gals. The RPM was set at 2700 for take off but no mention of the manifold pressure used. Full flaps were used. They flew it off at 86 MPH. Not sure I can get any where close to that in AH for the same weight and with the RPM limitation.
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2700 is the max RPM. I don't see how that's a limitation. :headscratch:
At 12400 lbs, full flaps, 2700 RPM, 53" manifold pressure, the AH F6F -5 takes off at 78 mph. :airplane:
Jdbecks I'm not aware of any changes to the pitot tube but I'm not an F6F expert. Because of the IAS inaccuracies there is a controversy regarding the F6F's true top speed. Some people think it was as fast or faster than the F4u but I don't recall which models they were comparing.
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Jdbecks I'm not aware of any changes to the pitot tube but I'm not an F6F expert. Because of the IAS inaccuracies there is a controversy regarding the F6F's true top speed. Some people think it was as fast or faster than the F4u but I don't recall which models they were comparing.
If memory serves me correctly, they had already moved on to the F7F & F8F , the F6f (all series ) pitot tube was never relocated, except in the tests that took place near the end of the war or post war......
I recall reading they found inconsistencys when doing the F4U vs F6f side by side performance/speed tests...where the F6f-5 was nearly identical as far as speed goes to the F4U ( I forget which version of F4U they was using )
however don't quote me or refer to my above post.. I have not researched/reviewed any of this stuff since 95/97 back when I was doing a write-up on the F6f-3 for AirWarrior Sim
hope this helps..
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The F6F-5's stall speed was 78 Kn (85 mph) how can it take off at a lower airspeed? The maximum spped of the F6F was 330kn it was powered by a 2000hp PW R2800-10. The F4u-1a had a 2250hp PW R2800-8 with a max speed of 380kn.
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No aircraft has one stall speed. The stall speed varies according to weight and configuration. If you read this thread carefully you might notice that.
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The F6F-5's stall speed was 78 Kn (85 mph) how can it take off at a lower airspeed? The maximum spped of the F6F was 330kn it was powered by a 2000hp PW R2800-10. The F4u-1a had a 2250hp PW R2800-8 with a max speed of 380kn.
heya Flushed, what are you looking at for your info?
Grumman & Chance Vought did some test near the end of the war or after ( post war ) and found that although the planes were identical or near identical in level flat out speed, their guages were showing (2) different readings, the F6f-5 was showing lower readings than the F4U.....
I will try an go dig up this test/info, so I have something to reference than just my memory....
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I know that FLS but the stall speed I gave was a clean aircraft with 25% fuel. So when you start adding bombs, rockets, ammo, more fuel what happens? so, I'll ask again how do you take an airplane off below the stall speed of one that has no armaments and only 25% fuel.
http://www.history.navy.mil/branches/hist-ac/f6f-5.pdf
Copy of report from a comparison test using an FW-190, F4U-1D, F6F-3
http://home.comcast.net/~markw4/index1.html
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Thanks for the link Flushed(wgmount)
notice on page 2 of that pdf file that it says max speed (mil) for the F6f-5 is 380
and on page 6 of the same pdf file it shows 330 knts at 23,400 ft w/ (1) 150 gallon external tank loaded
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Thanks for the link Flushed(wgmount)
notice on page 2 of that pdf file that it says max speed (mil) for the F6f-5 is 380
and on page 6 of the same pdf file it shows 330 knts at 23,400 ft w/ (1) 150 gallon external tank loaded
take a look at this: http://www.youtube.com/watch?v=hQ55LmRwkQg
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take a look at this: http://www.youtube.com/watch?v=hQ55LmRwkQg
what am I looking for? that video is showing an F6f-3 btw
I first saw this video back in the 90's when it was on Zeno's Warbirds website
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I know that FLS but the stall speed I gave was a clean aircraft with 25% fuel. So when you start adding bombs, rockets, ammo, more fuel what happens? so, I'll ask again how do you take an airplane off below the stall speed of one that has no armaments and only 25% fuel.
http://www.history.navy.mil/branches/hist-ac/f6f-5.pdf
Copy of report from a comparison test using an FW-190, F4U-1D, F6F-3
http://home.comcast.net/~markw4/index1.html
If you read carefully you'll notice that the lower speed was with full flaps. That's why I mentioned configuration as well as weight. So far the AH performance has matched the POH.
I don't know if it's a factor in this case but you also have ground effect when taking off.
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The film is wrong. It should be obvious that the take-off speed cannot possibly be 15 MPH less than landing condition, power-off stall.
The plane in the film was a very early F6F-3 (note the cockpit windows and two lower cowl flaps that were eliminated after Bu No 39999), so it was an introduction to the airplane. It is certainly not reference material or applicable to the model in Aces High. There are many inconsistencies in airspeed indicating with the F6F, as others have noted, and it shows in this film.
The AH model looks to be an excellent representation, based on the original F6F-5 test report.
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Search the BBS for HiTech's responses to tedious challenges of this sort.
You're not the first to think he found something no one else has ever considered.
I'm guessing HiTech has done a bit more research than you.
HONK!
Gooss
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About 60 Knots translats to about 70 MPH but I noticed that the F6F I flew with 25% fuel was about 100 MPH to get off the gound. that's a major difference to me.
You will never enjoy this game
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You will never enjoy this game
Your statement is 100% wrong. I have a great time with my squad. I have enjoyed playing this game and others like it for the last 30 years.
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What sim were you flying in 1980?
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What sim were you flying in 1980?
B727-200 Eastern Airlines.
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Did you get any kills? :D
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Your statement is 100% wrong. I have a great time with my squad. I have enjoyed playing this game and others like it for the last 30 years.
I'm curious, If you have been playing games like this one for 30 years, you must have played Air Warrior from the beginning? Do you recall that it had Full and Relaxed Realism arenas? If so you will recall that even full realism then was a lot worse than we have now. Games like Falcon3 boasted the most realistic flight model publically available, claiming that some of the code in the Hi Fidelity flight model was used in military simulations, but even that flight model was flawed. Any flight model in any game you or I have ever owned can be picked apart for some reason or other... Since we have both been doing this for 30 years, we both know that...
So I'm curious, after 30 years of seeing the same claims, why have you suddenly lost your balance over this now?
Badboy
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I'm curious, If you have been playing games like this one for 30 years, you must have played Air Warrior from the beginning? Do you recall that it had Full and Relaxed Realism arenas? If so you will recall that even full realism then was a lot worse than we have now. Games like Falcon3 boasted the most realistic flight model publically available, claiming that some of the code in the Hi Fidelity flight model was used in military simulations, but even that flight model was flawed. Any flight model in any game you or I have ever owned can be picked apart for some reason or other... Since we have both been doing this for 30 years, we both know that...
So I'm curious, after 30 years of seeing the same claims, why have you suddenly lost your balance over this now?
Badboy
I haven't lost my balance. I asked for help in the help forum for the specifics about how to set maneuvering flaps in the P38 when the POH says 1/2 flaps, what setting in AH provides the benefits of a lower stall speed and increased lift. Murdr answered the question. I did ask in another forum the "Wish" forum that the model of the P38 for flap deployment be changed to be more accurate. If asking for help or making a "Wish" post makes one unbalanced in your eyes, so be it.
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I asked for help in the help forum for the specifics about how to set maneuvering flaps in the P38 when the POH says 1/2 flaps, what setting in AH provides the benefits of a lower stall speed and increased lift.
Perhaps you haven't noticed that the way you have been posing your questions, with reference to the POH, and particularly in view of your other threads, has unfortunately given the impression that your questions are disingenuous.
It could easily appear as though you were simply looking for another way to pursue your explicitly stated agenda for modelling changes. I have to confess, it certainly didn't look to me as though you were genuinely seeking help.
But, if you are, I can tell you everything you could possibly wish to know about the flaps on the P-38 in Aces High. I have EM diagrams for the P-38 in almost every configuration possible in the game, and I can tell you the sustained turn rate and radius for every flap setting possible in the game and explain how to optimise those settings for the kind of fight you are in. But here is the thing… Most folk who ask genuine questions are actually interested in that kind of information, they want to optimise their performance in the game, but you seem to be more interested in comparing with the POH.
So, if you really want to know how to work the flaps in AH to optimise performance in the game, I can help… Your call.
Badboy
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Perhaps you haven't noticed that the way you have been posing your questions, with reference to the POH, and particularly in view of your other threads, has unfortunately given the impression that your questions are disingenuous.
It could easily appear as though you were simply looking for another way to pursue your explicitly stated agenda for modelling changes. I have to confess, it certainly didn't look to me as though you were genuinely seeking help.
But, if you are, I can tell you everything you could possibly wish to know about the flaps on the P-38 in Aces High. I have EM diagrams for the P-38 in almost every configuration possible in the game, and I can tell you the sustained turn rate and radius for every flap setting possible in the game and explain how to optimise those settings for the kind of fight you are in. But here is the thing… Most folk who ask genuine questions are actually interested in that kind of information, they want to optimise their performance in the game, but you seem to be more interested in comparing with the POH.
So, if you really want to know how to work the flaps in AH to optimise performance in the game, I can help… Your call.
Badboy
Murdr has provided the most authoritative response to my question. One question that I still have and perhaps you have the answer or can point me to a source is. The flaps on the P38 when extended added how much square footage to the effective wing area?
thanks
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The flaps on the P38 when extended added how much square footage to the effective wing area?
If you are trying to do some calculations, increased values of coefficient of lift with the Fowler flaps extended were always based on the area of the basic wing. So if you have Lift and Drag polars for the P-38's Fowler flaps the calculations should be done based on the 327.5 square ft. However, the area of the extended Fowler flaps on the P-38 is 42.6 square ft.
Hope that helps.
Badboy
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If you are trying to do some calculations, increased values of coefficient of lift with the Fowler flaps extended were always based on the area of the basic wing. So if you have Lift and Drag polars for the P-38's Fowler flaps the calculations should be done based on the 327.5 square ft. However, the area of the extended Fowler flaps on the P-38 is 42.6 square ft.
Hope that helps.
Badboy
Thanks, so 42.6 square feet divided by ½ is 21.3 Square feet or the amount of flap described by the POH that yields the best benefits of increased lift and reduces stall speed for the Combat or Maneuvering flaps.
In AH that 42.6 square feet is divided into 5 equal segments of 8.52 Square feet each.
Hit the “Q” key one time and you get 8.52 Square feet of flap
Hit the “Q” key again and you have 17.04 Square feet deployed
The third tap of the “Q” key gives you a total of 25.56 Square feet.
Fourth Notch of flaps provides you with a total of 34.08 Square feet of flap
Fifth Notch of flaps provides you with a total of 42.6 Square feet
So the closest flap setting within the game to the POH recommended combat flaps setting is either the second or third notch. Which is what Murdr provided in his response. He suggested the second notch for airspeeds between 225 and 250 and the third for speeds below 225.
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So the closest flap setting within the game to the POH recommended combat flaps setting is either the second or third notch.
The flap positions in the game are at 0, 0.2, 0.4, 0.6, 0.8 and 1.
The 0.5 setting clearly falls between 0.4 and 0.6 the second and third position.
So the area wasn't really needed to arrive at that conclusion.
Badboy
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The flap positions in the game are at 0, 0.2, 0.4, 0.6, 0.8 and 1.
The 0.5 setting clearly falls between 0.4 and 0.6 the second and third position.
So the area wasn't really needed to arrive at that conclusion.
Badboy
I understand that, but I wanted to know what the area of Square Footage of the total flap available was and what the area of 1/2 was.
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I understand that, but I wanted to know what the area of Square Footage of the total flap available was and what the area of 1/2 was.
Imo, the only reason to worry about this stuff is if you are actually coding the physics of a flight sim. :headscratch:
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I understand that, but I wanted to know what the area of Square Footage of the total flap available was and what the area of 1/2 was.
Why?
I already explained you wouldn't need it if you wanted to do lift/drag calculations and you didn't need it for the calculation you presented... So I'm curious what you want it for?
Badboy
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Imo, the only reason to worry about this stuff is if you are actually coding the physics of a flight sim. :headscratch:
Not really, I wanted to know the difference between the POH recommended flap setting of 50% flap for Maneuvering or Combat flap on the P38 and what is available within AH either 40% or 60%. I wanted to know what the difference of flap square footage was involved.
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Not really, I wanted to know the difference between the POH recommended flap setting of 50% flap for Maneuvering or Combat flap on the P38 and what is available within AH either 40% or 60%. I wanted to know what the difference of flap square footage was involved.
I understand what you wanted to know. My point was it doesn't matter and won't help you fly better by knowing specific flap surface areas.
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Hitech cleared this up in the other identical thread. The flap graphic and indicator position does not necessarily represent the actual amount of flap modeled for that position. In other words you can't take the full travel and divide it equally even though it looks like you can.
The question of what setting equals 50% extension is still open but I wouldn't be surprised to find that it's the third notch of flaps.
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Not really, I wanted to know the difference between the POH recommended flap setting of 50% flap for Maneuvering or Combat flap on the P38 and what is available within AH either 40% or 60%. I wanted to know what the difference of flap square footage was involved.
Again...
Why?
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Again...
Why?
I wanted to know the difference between the POH recommended flap setting of 50% flap for Maneuvering or Combat flap on the P38 and what is available within AH either 40% or 60%.
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Just noticed the airspeed thread has morphed into the flaps thread. :headscratch:
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I wanted to know the difference between the POH recommended flap setting of 50% flap for Maneuvering or Combat flap on the P38 and what is available within AH either 40% or 60%.
Again...
Why?
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Why not?
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I bet when he was a kid he was VERY picky about stuff like Kung-Fu Grip GI-Joe not being able to fly the helicopter
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Yes but Kung-Fu Grip GI-Joe could hang from the skid all day. You have to keep your perspective and go with your strengths.