Quote:
Originally Posted by Crumpp
To simulate the buffet realistically, the aircraft turn performance should be reduced if one tries to fly in it.
It takes more power to fly in the buffet than it does in smooth air.
The harder an aircraft buffets and more stall warning it delivers, the more power it takes to produce the buffet.
This is exactly why you see aircraft with little to no stall warning and the advent of artificial stall warning devices like stick shakers. With the advent of stick shakers, designers are freed from providing aerodynamic stall warning and can maximize aerodynamic performance.
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We have been here before ! As has been stated before Buffet has depth. The very first onset is referred to as the the "Buzz" or the "Tickle" The current RAAF PC-9 Flight manual uses the term "Light Pre Stall Buffet". It is a standard technique (and was in WWII as stated by Geoffery Wellum in his book First light) when trying to get the best out of the aeroplane to smoothly pull to then hold on the "buzz". This is a STANDARD technique taught in most air forces even to this day. Whole training sequences in Military pilots courses are devoted to max performance turning. It is also a standard technique used by Glider pilots trying to get the best out of their machines as well in the thermal centering etc.
Stick Shakers are a relatively new device and have little to do with WWII era aviation. Stick shakers were designed to provide Stall warning as a primary goal
not as a device to enable max performance turning..... AOA indicators do a better job in this department. Trying to fly an aeroplane on the shaker (like in a wind shear or GPWS event) is not an easy task as you are in and out of the shaker all the time. In general Stick Shakers are the preserve of the larger transport types from say the DASH 8, B757,B767 with conventional non FBW flight controls. Though some predominately Russian fighter types with conventional flight controls (early MIG29) do have similar devices (including pedal shakers) to provide Max AOA cueing.
We all know flying in deep buffet requires more power. I think you will find Energy bleed in CLOD is increased quite significantly IN the buffet.
Flying on the buzz is a valid technique to get the best turn performance out of the aeroplane.
I posed a situation before when this was the subject of another of these Mammoth "intellectual" threads... the answer was avoided. Picture this situation.
You find yourself in your Spitfire MKI 90 degrees nose down at very low altitude. You are not sure if you have the turning room to avoid the ground.
Your only chance is to get the absolute minimum radius turn RFN... how are YOU going to fly the turn .. no time to think ... delay compounds the issue.... FAILURE = DEATH.