Brantel
Well Known Member
Does anyone think that ground effect could be well effecting my AOA during the flare to land?
I have done at least 50 stalls at alt in my RV7 and my Dynon AOA indicator and beeper/buzzer always indicate a stall at altitude about 1 red bar above the yellow and the progressive beeper always goes to a solid tone about right when the buffet happens. Full or no flaps, the indications are real close to the break. This tells me my calibration is dead on...at altitude!
When I land in a three point, the Dynon is still well in the yellow and the beeper is still intermittent even at touchdown. No full tone and the AOA is still in the yellow.
I would expect to hear full tone right at the point where all wheels hit the runway or sometimes I drag the tailwheel slightly before the mains and I would expect the AOA to be indicating stall at this point.
Does anyone think that ground effect will screw with the AOA of the Dynon since they take their delta readings on the pitot?
I normally hit full flaps just prior to turning base, hold 75-80kts till base to final, hit 70-75kts early final and 65-70kts on close final over the fence. The decent rate can be really high at 65kts depending on loading...my plane seems to stall at altitude right on Van's published numbers when I use TAS as the reference. IAS is lower than Van's numbers.
My AOA indicates about mid green zone on the deadly base to final turn @ 70-75kts maybe a little higher if light and maybe a little lower if heavy. +-1 bar variation.
I have been working on my short field techniques and trying to reduce my speed across the threshold. CS equiped planes really have an advantage here...seems with the FP, there is a point where you fall off the cliff on decent rate and you need some energy to arrest that at the bottom. Keeping the speed up stops this but leads to longer rollouts.
All of this has me thinking that an RV7 FP can be well on the backside of the power curve, in the area of high decent rate but still be well above the critical AOA. One of you smart engineers might explain all this...
Sorry for the ramblings, I am navigating thru one of the corners of my plane's performance envelope that is critical to short field operations and I have no intentions of wrecking me or my plane!!! I don't like the feeling of being too far on the back side of the curve since a loss of engine in this area most likely means your landing on the fence or the ILS antenna array or worse at some fields and most short ones.
I have done at least 50 stalls at alt in my RV7 and my Dynon AOA indicator and beeper/buzzer always indicate a stall at altitude about 1 red bar above the yellow and the progressive beeper always goes to a solid tone about right when the buffet happens. Full or no flaps, the indications are real close to the break. This tells me my calibration is dead on...at altitude!
When I land in a three point, the Dynon is still well in the yellow and the beeper is still intermittent even at touchdown. No full tone and the AOA is still in the yellow.
I would expect to hear full tone right at the point where all wheels hit the runway or sometimes I drag the tailwheel slightly before the mains and I would expect the AOA to be indicating stall at this point.
Does anyone think that ground effect will screw with the AOA of the Dynon since they take their delta readings on the pitot?
I normally hit full flaps just prior to turning base, hold 75-80kts till base to final, hit 70-75kts early final and 65-70kts on close final over the fence. The decent rate can be really high at 65kts depending on loading...my plane seems to stall at altitude right on Van's published numbers when I use TAS as the reference. IAS is lower than Van's numbers.
My AOA indicates about mid green zone on the deadly base to final turn @ 70-75kts maybe a little higher if light and maybe a little lower if heavy. +-1 bar variation.
I have been working on my short field techniques and trying to reduce my speed across the threshold. CS equiped planes really have an advantage here...seems with the FP, there is a point where you fall off the cliff on decent rate and you need some energy to arrest that at the bottom. Keeping the speed up stops this but leads to longer rollouts.
All of this has me thinking that an RV7 FP can be well on the backside of the power curve, in the area of high decent rate but still be well above the critical AOA. One of you smart engineers might explain all this...
Sorry for the ramblings, I am navigating thru one of the corners of my plane's performance envelope that is critical to short field operations and I have no intentions of wrecking me or my plane!!! I don't like the feeling of being too far on the back side of the curve since a loss of engine in this area most likely means your landing on the fence or the ILS antenna array or worse at some fields and most short ones.
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