EFATO

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Okay, I've got the plane reserved for Saturday morning. The weather looks good and I'm keen to explore some of the EFATO turnback issues discussed here.

Please critique my "test plan".

Key numbers from the POH:
Vs = 63 knots (at MTOW)
Vbg = 78 knots (at MTOW) - supposedly yields a 1 in 8.7 glide ratio, and a V/S of ~900 ft/min (to confirm)

Vs in a 45 degree stable descending turn is thus theoretically ~75 knots. Close enough to Vbg to not need to explore the difference in performance between pulling to the stall at 45 degrees, and flying Vbg at 45 degrees. In fact (but to be confirmed) I expect the stall warner to sound continuously, with noticeable buffet, in a 45 degree Vbg stable turn.


Preliminary actions:

HASELL

(i) From height, establish the aircraft in a Vbg stable, trimmed descent. Mark attitude with some sticky tape on the canopy. Write down/time V/S.
(ii) From height, establish the aircraft in a Vbg stable, trimmed descent at 45 degree bank left and right. Mark attitude again with some sticky tape. Write down/time V/S.
(iii) From height, establish the aircraft in a Vbg stable, trimmed descent with the mixture closed. Write down/time V/S.

(i) and (ii) are so that the proper attitude for the subsequent tests can be set quickly. (iii) is to provide data on the difference between throttle closed and mixture closed (prop windmilling), so that all subsequent data points can be corrected for that.

Test items:

All items start from a stable, properly trimmed Vy climb along a line feature, into the wind as far as possible. When passing through a certain safe height (3000' most likely, weather permitting) I'm going to pull the power and:

a. Hold the nose up to see how long it takes for the aircraft to stall. Then recover the stall and see how much time/altitude I lose before in a stable Vbg glide.
b. Hold the stick in the same position, furthermore as in (a).
c. Completely release the stick, let the aircraft sort itself out, furthermore as in (a).
d. Fly the aircraft in a half-G pushover, furthermore as in (a).
e. Fly the aircraft in a ballistic arc (zero G), furthermore as in (a).

(a)-(e) are essentially to see how much "oh ****" time I've got, and how important ingrained reflexes are. If, for instance, (a) delivers the same as (d)/(e) (which I don't expect), the "oh ****" factor isn't all that important.

Subsequent tests include one second of "oh ****" time after closing the throttle, then:

f. Establish Vbg according to the best technique from (a)-(e), then turn into the crosswind 225 degrees at 45 degree bank, turn the other way 45 degrees at 45 degree bank.
g. Same as (e) but with 60 degree bank
h. Same as (e) but with 30 degree bank

(g) and (h) essentially to confirm Rogers

i. Like (f) but start with a left turn 45 degrees away from the crosswind, then turn 225 degrees into the crosswind (teardrop thus reversed). Altitude lost should be the same as (f), but you never know.

j. Like (f) but this time roll into a 45 degree bank while pushing the nose down (at half or zero G as appropriate), ready to pull as soon as the Vbg attitude has been set.

k. Like (f) but use the Mark1234 technique of immediately rolling to 60 degrees bank, pull to the stall warner while the nose drops, play angle of bank against stall once the nose is at the Vbg attitude.

At the end of all items a-k, write down altitude lost.

Further things to note: QNH, OAT, actual weight, actual wind. I will also run an outdoor-type GPS which has track recording so that I can see how big the teardrop shapes are and whether the 225/45 turn without any pause inbetween gets you aligned with the runway centerline. (Any suggestions on how to make sure I'm later able to correlate the GPS track with the test results that I wrote down? Other than making sure my watch is synced with the GPS time, and write down the time of each individual test?)

Any tips on record keeping? Anyone has a handy form or something for this kind of stuff?

Other safety items:
I'll be doing this in the R2160 which is cleared for aerobatics, will be flown within the "A" limits, and I am very current in aeros/spin recovery etc. in this aircraft. I have in the past pulled the mixture to ICO in-flight and I know the engine will windmill above Vs and catch immediately as soon as mixture is restored. Everything will be done at altitude, over an area with plenty emergency landing opportunities. Airspace will be the Rotterdam TMA (class E) with permission/traffic service from ATC.

Any additions?