While applying my contact points fix, Mark Aisthorpe at simhq-forums discovered something terribly wrong in the aircraft.cfg of the stock Grumman Goose in FSX.Just look at this:[Reference Speeds]flaps_up_stall_speed = 60.0full_flaps_stall_speed = 87.0It appears they mixed those values up. The Beaver (and I think all other planes) has it the other way round.Any comments?

The reference tab on the kneeboard:VS - Stalling Speed (max weight, flaps up) 70 MPH VSO - Stalling Speed in Landing Configuration 60 MPH That seems to make more sense. The aircraft.cfg cannot be correct in this aspect.Jozef K. http://homepages.onsnet.nu/~jkusters/signature.jpg

As the 60 mph seem to fit, I'll stay with switching the values so far, as I don't know how weight is taken into account.However, this would be something definately worth a fix in a patch, as it's not just cosmetical but essential for flaps operation.Edit:Just had a look at the DC-3.For the DC-3 example:Reference sheet:Vs = 77 mph Vso (landing) = 71 mphaircraft.cfgflaps up = 67.5 ktas = 77.7 mphfull flaps = 61.5 ktas = 70.8 mphEdit:Did the same calculations for the Beaver, reference and aircraft.cfg match about as good as the DC-3.Therefore, I think it's safe to assume that putting in the reference sheet values should be ok, unless someone has proof for the reference sheet values to be wrong.I could imagine someone notices the Goose stall to early and then increased the wrong value. Or perhaps someone calculated from mph to knots, although the sheet already gave the speed in knots.Edit!The reference sheet for the Goose is in MPH as well. I'll do the calculations at once and give the correct values for the aircraft.cfg!From the Goose reference:Vs = 70 mph = 80.55 ktVso (landing) = 60 mph = 69.04 ktThus putting the aircraft.cfg toflaps_up_stall_speed=80.5 full_flaps_stall_speed=69.0 should get it close to the real values.

There is something wrong with the mph to kts conversion here. The numerical value for Knots must be less than the numerical value for mph as a nautical mile is longer than than a statute mile.I've forgotten the conversion factor (cause I come from a metric land down under). But I seem to remember from days long ago that the conversion factor was 1 nautical mile = 1.15 statute miles. Thus the inverse conversion factor is 0.869. Using the speeds given, 60MPH = 52.17KTS and 70MPH = 60.86KTS.Tell me if I'm wrong.

Well, three times calculated right, but when it's important, I mixed the figures (6076 ft and 5280 ft).Now this should be correct now:70 mph = 60.83 kts60 mph = 52.14 ktsI accidentially reversed the factors.New stall speeds should be:flaps_up_stall_speed=61.0full_flaps_stall_speed=52.0Sorry for that.PS: This makes the full flaps stall speed the only really wrong value. But this even more.

Check out this freeware units converter. I use it all the time, it's awesome - http://joshmadison.net/software/convert/Well, perhaps "awesome" is a little over the top. But I do use it a lot.Hmm, wonder how the message got doubled, I only hit the button once.Anyway, thanks for the tip!, btw.Hmm, the cruise speed seems a little slow, too, wouldn't you say? (I haven't check any other reference)Thomas[a href=http://www.flyingscool.com] http://www.flyingscool.com/images/Signature.jpg [/a]I like using VC's :-)N15802 KASH '73 Piper Cherokee Challenger 180

Check out this freeware units converter. I use it all the time, it's awesome - http://joshmadison.net/software/convert/Well, perhaps "awesome" is a little over the top. But I do use it a lot.Thomas[a href=http://www.flyingscool.com] http://www.flyingscool.com/images/Signature.jpg [/a]I like using VC's :-)N15802 KASH '73 Piper Cherokee Challenger 180

>>>>However, this would be something definately worth a fix in a patch, as it's not just cosmetical but essential for flaps operation.80.000000Note that you

So why are those lines in there?Do we need to add the three lines you highlighted? Are the values of Cl max in table 404 and 1545 incorrect? Do they need to be changed? To what?Thanks for the very informative posting. I'm always amazed by how little I know about how this software works,Thomas[a href=http://www.flyingscool.com] http://www.flyingscool.com/images/Signature.jpg [/a]I like using VC's :-)N15802 KASH '73 Piper Cherokee Challenger 180

>>>>So why are those lines in there?<<<

Hi,As I understand it, in FS9 they are used by the flight planner to calculate the leg times, and the flaps up stall speed seems to be used by the AI aircraft to help determine the takeoff rotation speed.Hope this helps,--Tom GibsonCal Classic Propliner Page: http://www.calclassic.comFreeflight Design Shop: http://www.freeflightdesign.comDrop by! ___x_x_(")_x_x___

Some add on programs require data which is not actually necessary for the correct operation of the aircraft in FS.One that does, for example, is FS HotSeat (the virtual co-pilot add on), very often you have to add specification data to aircraft files in FS if you want to use them with FSHS as the program uses this data to calculate flight plan data andhow well you did for your evaluation etc. The programmers of FSHS recommend getting these values from airliners.net (or somewhere similar).

>>The Vs and Vso speeds in the reference_speeds section are just>window dressing, they have no effect on airplane performance.>In the FS9 SDK MS identifies them as being used by FSEdit; in>the FSX document they are said to be:

>>>>As I understand it, in FS9 they are used by the flight planner to calculate the leg times, and the flaps up stall speed seems to be used by the AI aircraft to help determine the takeoff rotation speed.<<<>>>Which is usless, since FSEdit no longer exists. It hardly worked when it was supplied.<<<