Thank you Deliv. No, I am not mental. My comments are based on an A grade in Maths Mechanics A Level, 1st Class Honours in Aero Eng from one of the big 3 universities, RAF wings, the teaching received from a number of OCU/frontline instructors and experience.
Sarbloke. An object with zero groundspeed has zero KE wrt the Earth.
How can a pilot flying on instruments subconciously increase IAS
I actually said thrust. Whilst carrying out your selective radial scan, you carry out numerous tiny corrections, and when experienced will do so without a great deal of concious decision making. Under the circumstance I've described the pilot may have nibbled the throttle open without ever having conciously decided "I'm going to open the throttle".
When flying an approach, do you still make big concious power/attitude decisions like a first solo stude or do your inputs 'just happen', subconciously, like when riding a bike?
How windshear affects IAS:
Imagine model plane flying steadily with zero groundspeed, 20 kt IAS in front of a fan.
Fan is suddenly turned off.
Model plane is suddenly at zero airspeed, will lose height rapidly and either crash or accelerate to a suitable airspeed to fly away before it hits the floor.
Not the same as the downwind turn in steady strong wind case - as succinctly described above, aircraft flies with reference to the air
Yes correct about windshear. But are you (plural) trying to say that sometimes GS is relevant (above) and sometimes it isn't (turning)?
As I said- you're sitting in front of a computer- do a little research and find one authorititive confirmation of the "Down wind turn" and I'll eat my shorts!!!
To quote John Farley, no less:
On the other hand, if the air is not still, but moving at a steady speed over the ground, the aircraft will suffer a fluctuating ground speed after the “steady ” turn is established at “constant” airspeed. This ground speed (and its related kinetic energy) will be a minimum when flying into wind and a maximum when downwind.
This energy change and the problems it produces (thanks to inertia) is what is at the heart of the so-called downwind turn stall issue. I say so-called because this effect (while always having some transient effect on airspeed, related to the transient change in ground speed) will only cause a STALL in quite EXTREME CIRCUMSTANCES. Normally there will be no more than a minor reduction of height or a slight loss of airspeed (both usually so small that I recommend you don’t even think of wasting your time airborne by trying to measure them in real air, which is anything but steady)
(Google 'downwind turn airspeed' and you'll find two ancient cached pprune pages. The above paragraph is from the thread begining 'among light aircraft pilots...')
How would you like your shorts cooked Deliv?
I reiterated that what I have described is a transient effect, negligible in normal circumstances, light winds and gentle turns but it exists.