T-6 in thin air.

[Ron Attwood]

I'm smug enough to think I can land a T6 pretty efficiently...Until last night! Taking off from Jackson Hole (KJAC) 6,700ft. was the first indication that all was not well. 3kt crosswind (no big deal) saw me having to bludgeon, cajole and threaten TSIX off the ground. Not a pretty sight I can tell you. I did a circuit and landed...Sort of. Ended in a ground loop and loss of face in front of a cackling crowd of ne'er-do-wells. After the hilarity subsided, some offered the theory that in this rarified atmosphere rudder and control surfaces would be less effective. Mmm I thought, makes sense. So I tried again and got the same result.
Not so smug now eh?

My question is, is accusim really that deep?

Discuss.

[DHenriques_]

I'm smug enough to think I can land a T6 pretty efficiently...Until last night! Taking off from Jackson Hole (KJAC) 6,700ft. was the first indication that all was not well. 3kt crosswind (no big deal) saw me having to bludgeon, cajole and threaten TSIX off the ground. Not a pretty sight I can tell you. I did a circuit and landed...Sort of. Ended in a ground loop and loss of face in front of a cackling crowd of ne'er-do-wells. After the hilarity subsided, some offered the theory that in this rarified atmosphere rudder and control surfaces would be less effective. Mmm I thought, makes sense. So I tried again and got the same result.
Not so smug now eh?

My question is, is accusim really that deep?

Discuss.

There is "magic" in Accusim LOL

I trust you made the usual density altitude corrections such as leaning during the line up check at power to get your ear into the max power available equation?
The main thing to remember about density altitude is as we like to say in the aerobatic display business............
"Indicated airspeed is indicated airspeed. True airspeed is always higher! "
As for Accusim, who REALLY knows what devilment the guys are up to late at night when the rest of you are all asleep.
The SHADOW knows !!!!!!!!!!!!!!!!! ))))))))))))))))
Dudley Henriques

[Lewis - A2A]

Yes there will be some issues for you, as Dudley says the engine is number 1 and Accu-sim will definitely be at work there as the sim lets our sim engine know what altitude its operating at.

thanks,
Lewis

[Ron Attwood]

I fully understand altitude v engine behaviour, that's a given, but altitude v aerodynamics? Yes I was properly leaned out. I'll have to try it again. In the meantime a gratuitous screen shot from a separate session. #4 is just working his way into the diamond. Gunter is leader, I'm #1, Nick Wood #2 and Mike McEwan #4



All A2A Spitfires of course.

[Ron Attwood]

For the record. Accusim is so bloody accurate that it even takes into account excess smug. It's well known in aviation circles that too much smug can, and usually does, lead to huge expense and loads of form filling. IF you're lucky!

[Oracle427]

For the record. Accusim is so bloody accurate that it even takes into account excess smug. It's well known in aviation circles that too much smug can, and usually does, lead to huge expense and loads of form filling. IF you're lucky!

Amen to both those points!

[Lewis - A2A]

lol great points Ron, and beautiful shot of you guys forming up!

[Oracle427]

I had never tried pattern work in the T6 at altitude. It sure is different and you have to work the rudder that much harder to remain in control. I agree that the rudder feels less effective during the rollout. The ground speed is so much higher so it looks strange.

I then decide to do a few cubans and loops and was surprised at how quickly the ground rushed up and I was nervous about pulling to hard and stalling.

I even got a surprise with a slight wing drop during an overly aggressive climbing turn to the crosswind leg.

It is great to see the difference in handing being modelled. I'm going to have to do this more often.

[DHenriques_]

I had never tried pattern work in the T6 at altitude. It sure is different and you have to work the rudder that much harder to remain in control. I agree that the rudder feels less effective during the rollout. The ground speed is so much higher so it looks strange.

I then decide to do a few cubans and loops and was surprised at how quickly the ground rushed up and I was nervous about pulling to hard and stalling.

I even got a surprise with a slight wing drop during an overly aggressive climbing turn to the crosswind leg.

It is great to see the difference in handing being modelled. I'm going to have to do this more often.

We deal with density altitude all the time in the airshow industry. Its killed a lot of good pilots. Vertical maneuvers are especially prone to danger as reaching an entry IAS takes longer, everything on the vertical line both airplane and engine is degraded and since TAS is higher for the same IAS, your turn radius is extended.
Our pilots seriously curtail their high density altitude show maneuvers, especially energy loss maneuvering such as snaps and gyroscopics.
What you might get away with at sea level will most likely kill you on a hot day at high DA.
Dudley Henriques