But what about aeros? If an aeros manouvre goes wrong it can often result in a spin. Furthermore, since the spin wasn't entered deliberately and wasn't expected, it might not at first be obvious which way you're spinning.

Aeros are for aeros type people in machines designed and tested for it being taught by pilots that know what they are doing.

Same with the mill boys and girls.

Not for PPL's and CPL's fannying around in clapped out heaps with the blind leading the blind in the RHS.

Well said Jock.

G

Dirk,
I do understand. The thinking behind the 'minimum 30 degree bank' is that if you are too slow the first sign is a higher rate of descent which is easily recovered from by levelling the wings.
It also ensures that both wings are at almost the same speed so that one wing doesn't stall before the other.
Furthermore, there is less urge to 'rudder' the turn more to tighten it.

There is little tendency to pull harder as the turn onto final is usually 'high' as the final approach will usually be the time where final flap settings will be made or the airbrakes increased accordingly.

Most satisfying is the final turn flowing into a nice side-slip flowing into the flare and three point touch down.

I thought glider base are at 45 degrees to final anyway.

Anyway the best way to do it is by not having a base at all and just keeping a constant aspect all the way round from down wind.

The base would be at 45 degrees from the downwind leaving a 135 degree turn to final.
The 45/135 degree base/final turn is just a formalization of the old RAF constant aspect approach effectively allowing one to turn in early at any point along the way.
The problem with it being is fitting more aircraft into the circuit and different types' gliding/speed characteristics.

Strange that the safest, most environmetally friendly and reliable way to get down morphed into cross country circuits.

Hmmm. Back in the '70s at least at Barton, I don't remember there being such a 'brick wall' between 'aeros type' people and anyone doing a PPL. Often, on completing the PPL, aeros was the next logical step for some (indeed with some instructors and with interested students, you'd no doubt have done a bit of extra-curricular aeros during the basic training phase!). But it was a long time ago, and maybe I've forgotten exactly how it was.

mad_jock in post #13:
My father instructed in AT-6s during the big one (Harvard to my UK friends).

Part of the syllabus included IAS covered below 90 kt., so the student (WASPs in this case) learned to fly by feel, sound and attitude. Of course the instructor's pit still had a "live" IAS, but seldom was intervention called for.

And no, for the unwashed, this 600 hp taildragger had no stall warning!

I once got a flight in the front seat of a Stampe. It had stick, rudder, throttle, mixture, carb heat.... and a lot of instruments in that front cockpit. But all of instruments, every one, were paper cut-out ones glued onto the dash!

"That's all you need" said the guy in the back. He was right!

I suspect in the 70's at Barton the ratio of hairy arsed knows what they are doing occupants of the RHS to clueless idiots that couldn't find there backside without a mirror and a FMS was significantly different to today where the RHS may have only done 3-5 spins as part of their FIC.

Rofl!

Am I missing something here? You do your base leg getting further away from the airfield all the time?

Was I Lucky?...
 

Whilst doing some practice Power On 60deg Banked Turns in a C152, I caught up my own wake turbulence, and was spat out of the turn slightly over wings level and on a downward path.. Which was easily corrected.

I can only assume my upper wing encountered the turbulence and stalled, had the other wing stalled we would have been upside down in next to no time... Was I just lucky?

I don't think it would have stalled in a normal speed steep turn with a bit of turbulence off yourself.

What we are talking about to most PPL's and instructors is a rather extreme attitude. You really have to be trying to get anywhere near what we are talking about.

Which is another reason why I see it as a bit of a pointless exercise for the majority of pilots. I can see certain groups getting near it such as photo pilots and aero's but the majority of us won't get anywhere near it unless somebody makes us do it as part of an exercise.

No, you were unprecise and loosing altitude in your turn, otherwise the turbulence would have been below you. And wingrock is not stalled.

I disagree - it's quite common if flying at a steep bank angle in a slow aeroplane to hit your own wake vortex. The vortex does not descend very fast.

G

moose stall - some types in specific configurations and power setting will get the tailplane stalled if they fly through their own wake - sudden and violent nose down pitch. Numerous fatal accidents (can't shoot a coyote at high altitude).

I know that it is not uncommon, due to the reason, that it is not uncommon to descent unintentionaly in steep turns. What time do you need for a 360 in a C152? What is the span of a C152? Something like 33 feet? Most people will accept such a deviation in a steep turn as negligable. But loosing that altitude will bring you closer to your own wake, maintaining level keeps you out of it.

I know it is nitpicking, excuse my interruption.

Piper Classique,

The base would be a tangent to a circle with centre at threshold, the turn to base being started abeam the threshold.
So the base is actually a much more constant distance to the runway than your normal circuit.

If you think about aiming points and such, this is much easier to judge and adjust. Just a slight modification of a spiral where your aiming point would be completely constant, hence, constant aspect approach.

A 360 in a C152 at 60 aob could be done in around 15 seconds.

What is much harder to estimate of course is the behaviour of the wake vortex.

G

Another vote for being able to feel wake turbulence when doing 60 degree turns without losing height.

I have looked but not managed to find figures for how fast light aircraft wake vortices descend. I did find a suggestion that it was slower than a vortex from transport-sized aircraft. Or perhaps it's related to wing loading... same result. I'm afraid I've lost the link.

Do vortices initially descend? For example, if you were at the top of a loop, wouldn't your vortices actually go up? If so, then when doing a 60 degree turn your wing vortices will initially be cast off more laterally than downwards, and perhaps your outboard vortice will actually rise or stay level (in the pictures they always seem to diverge laterally outwards).