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TacomaSailor
December 29th, 2011, 15:37
I’ve requested a new IRIS forum username since the one I had used to post dozens of questions over the last several years is not authorized to post – despite my profile showing it is. The response was we are reviewing your registration. I suppose that may take a while – it being New Years and all.

So I’ll keep putting the questions here on this more than capable site.

At flight levels above 10,000' the C-27J speed tape, HUD, and FSX shift+z display of speed all suddenly go to 0 despite the GPS showing ground speeds of over 300 knots. This happens on most flights – in even clear skies.

I am pretty sure it is icing since I can descend to below the freezing level and the air speed returns to normal. I climb back up to the previous problem altitude and the 0 speed may or may not occur.

All the ice protection is turned on but the pitot tube still ices up.As I said – this occurs in clear air!

I have also encountered sudden ‘fall out of the sky’ stalls at flight levels and 275 KIAS when the speed SUDDENLY goes to 0 with a GPS GS over 300 knots. I am assuming FSX thinks the wings and control surfaces are also iced. I can usually recover from the stall when the plane descends into warm air and the air speed tape starts working again.

As I said – this occurs in clear air! The sudden stall only occurs in about 1/4 of the speed going to 0 episodes.

After recovering from the stall and climbing back to altitude the plane will not ever regain the speed it did have before the stall. For example


16000’ 265 KIAS Clear Sky –stable flight on AP/IAS/ALT/PLN for 20 minutes
Speed instantly goes from 260 to 0
I descend to 6500’ (sea level air temp=60F) and the speed suddenly returns to 280 KIAS
I climb back to 16000 but max speed attainable is 230 KIAS N1=94 N2=104
I continue at that flight level, those engine settings for 20 minutes – 230 KIAS

Has anyone else encountered this problem – speed going to 0 and sudden stalls from high speed flight?

C-27J being unable to regain speed after icing?

Does anyone have a suggestion for a fix?

UPDATE
16000' AP/ALT/IAS/PLN SpeedTarget=265 Max attained=232 Outside Air=+13F GPS GroundSpeed=335
The AC had been at that altitude and speed for 10 minutes - very stable

Using a standard aeronautical calculator the GS at that temp/PA should be 295 - not 335
-OR-
If the GS is really 335 then KIAS is actually 268 - 272

Switching to the KingAir 350 shows a KIAS of 280 which makes sense

SO - it appears the pitot tube is malfunctioning or the calculations are incorrect

Then very suddenly the speed tape went to 0 again!

N2056
December 29th, 2011, 15:50
Your issues regarding support have been repeated enough now. Please just run one thread for you problems from now on. Thanks!

TacomaSailor
December 29th, 2011, 15:54
How can anyone respond to a single thread that asks questions about

icing
throttles
autopilots
VOR

I will do what you ask but it is hard to understand

Roger
December 29th, 2011, 15:59
How can anyone respond to a single thread that asks questions about

icing
throttles
autopilots
VOR

I will do what you ask but it is hard to understand
It is the same aircraft...over and over. One thread would be nice I think...unless you would like to take over our entire FsX forum?

N2056
December 29th, 2011, 16:02
I think at least some of your problems are being worked on in this thread...Hope it helps!
http://www.sim-outhouse.com/sohforums/showthread.php?60873-C-27J-Spartan

fxsttcb
December 30th, 2011, 08:53
I think at least some of your problems are being worked on in this thread...Hope it helps!
http://www.sim-outhouse.com/sohforums/showthread.php?60873-C-27J-SpartanI agree that we need to try and keep all things C-27J related confined to a single thread.
Jumping back and forth between them while trying to help, and sort my own issues, is kinda confusing.
As in: Gee has this issue been addressed already elsewhere? Better search the other threads so I don't duplicate efforts.
It may be a little more work, for someone looking for help, to find it in a large thread, but, that's what the thread search option is for.
Also a single thread tends to remain visible with regular queries and fixes being actively discussed.

My nickel's worth(inflation):cool:...Don

warchild
December 30th, 2011, 16:11
yup.. Please do join us in the main C-27J thread above. I cant do anything about gauges, but theres a lot of eyes watching, and since i'm re-writing the FDE, i'll be making update posts about it in that thread only.. You'll want to be there so you can get your update when its finished ( which wont be too long in the over all scheme of things )...

Pam