Multi ASDA

[carbonfibre]

A question for multi instructors.

I recently renewed my Multi engine rating where an ASDA is called for, i backseated someone who renewed there IR. The examiner / instructor cut the fuel to the right engine while at take off power causing the aircraft to veer at approx 50 kts, the student then opened up the remaing throttle, for reasons unknown but to him instead of bringing the aircraft to a stop.

When I completed mine having seen this, immediatly on feeling the aircraft veer closed the throttles and brought the aircraft to a halt.

All this you say, no problem, what you've been trained to do, i agree, however the other student had to be relieved of control because of a dangerous situation, there was no brief that this kind of emergeny would be taken during the test at any stage, (I know it can be unexpected).

But after talking to another instructor, they thought that cutting the fuel was innappropriate and dangerous, and under guidelines from the JAA / CAA should not be tested like that. I was told then it should have been something like a car test, a shout STOP or a slap on the dashboard but most definatley not cutting the fuel.

Can anyone clarify :ok:

Many thanks

[eyeinthesky]

Interesting... A couple of points here.

1) Pre-warning of an emergency:

As you say, they may occur without warning, and if the instructor/examiner is sure that they can be completed safely as a surprise, then I see no objection.

2) Cutting fuel:

Certainly I would not cut fuel to simulate an engine failure on climbout, as I would rather know that the chances of the engine responding if necessary to an opened throttle were better than the chance of a problem getting the mixture flowing. (And also if you open the mixture from ICO with the throttle at full power surely that would be bad for the engine..?). However, if you are on the ground, below Vr, and an engine fails, you are not going anywhere, are you? You are certainly not going to bring the failed engine up again, so whether it is failed due a mixture cut or a throttle reduction makes no real difference.

I do not have reference to JAR here, but I think you are right that they do not recommend the actual shutting down of engines at low level through mixture cuts to simulate failure, rather through throttle reduction.

Of interest also is your observed victim's pre-take off brief. Did he go through the:

"In the event of an engine failure or other malfunction before xx kts I will close both throttles and stop etc..." ?

If so, he obviously forgot! If not, perhaps the examiner/instructor wanted to make a point about preparing for the unexpected and he certainly made an impression on you and probably the other bloke as well!!

[hugh flung_dung]

"Rejected take-off at a reasonable speed" has been listed as a mandatory part of the test for quite a while - BUT I don't normally do it.
With a light twin there is a VERY small window for the stude to react before heading divergence (and presumably nose leg stress) becomes excessive and, after a few surprises, I now believe it brings an unacceptable risk for little benefit. In the briefing I discuss engine failures during take-off and I ensure that I get a full verbal brief before line-up.

On a general note: the Lycoming info sheet about piston slap shows that it's much kinder on the engine to use mixture rather than wacking the throttle back. Because it takes slightly longer to get the power back if needed I normally use mixture above 3000ft (and on the ground), throttle below 3000 and occasionally fuel in the cruise.

HFD

[Keygrip]

HFD - it doesn't say anywhere (does it?) that the Rejected Take Off is as a result of an engine failure.

Why not do the drill - so that you can HONESTLY tick the box that says "Mandatory" - but just do it verbally from a few knots below Vr?

The RTO could be ATC induced, an open door, a system malfunction, a runway incursion - anything. It doesn't have to involve the fear of running off the runway, and you then also have a practical demonstration of how much runway it will need to accelerate and stop for real!!

[carbonfibre]

Aplogies,

Yes the student did go through the TO brief, however he was not familiar with the aircraft, no time on Seneca 2, all on BE76 and Seminole in US had a US / IR. He opened the throttle for what reason i dont know after the fuel was cut, overboost light came on instructor took contrtol, albeit within yeards of runway edge.

As for the JAA reference i have been told by a school that i currently doing my IR with that however it was done in the pre-JAA days(fuel cut off / throttle reduction) he has shown me paperwork but i cannot referenece it until i am back at the school wednesday, that use of fuel cut off / asymetric at high power settings is not used and that simulated i.e "stop" is prefered.

It did not affect my test as i would like to think that during the TO and approach to land as i have always been taught is the most demanding and dangerous, especially when IFR, Im always prepared to close throttles. The briefing i was talking about was the lack of by the examiner, regarding emergencies in general!! you had to be there really

All I thought at the time was, the student was not on the ball, fuel cut off, moving towards runway edge, things could have been far worse. I felt it unecessary to complete in this manner, as part of the test profile is the ASDA and its gonna come at the start or on a touch and go? so its going to be there.

PS it was not the impression that i wanted, i have 4 years of multi flying, and i thought that it was, errrring on the wrong side of safety, this was a ride for me to see his IR renewal and not the multi renewal.
Thanks for replies:ok:

[hugh flung_dung]

Keygrip:
You're right, it doesn't say that the RTO has to be from engine failure, apologies for giving a false impression.

If I shout STOP the stude close the throttles, puts the brakes on and taxis back for another go. This probably costs them 5 minutes (£20'ish), it certainly frightens the barbed wire fence at the end of the airfield (less than 800m), may damage the grass and is not terribly kind on the engines. There seems little point - it adds cost and risk for virtually no benefit.
In the brief I ask them what they would do if I or ATC call STOP during the TO, we then discuss the effect of an engine failure during the TO, I then make sure they give me the full TO brief before we get into the acft (and again during the checks) - more value with no increased cost or risk.

Something I DO insist on is an acceleration gate of 80% of lift off speed by 40% of TODR, if we don't achieve this I would expect the stude to stop.

Incidentally, the same form says that take-offs are optional!

HFD

[StrateandLevel]

Whats an ASDA? it used to stand for Acceleration Stop Distance Available, now known as EMDA!

Flight Examiners Handbook Principles of Flight Testing Para 3.2.3:

The requirement for the whole flight must be established by completing a thorough pre-flight briefing

i.e. Examiners must not throw things at the candidate if they have not been pre-briefed. That does not meant that you can't surprise them, but they must be forewarned that you intend to do so.

[whatunion]

cutting the fuel off, that sounds like the hallmark of a cowboy playing to the gallery.

i like the standard briefing our examiner always gave us before a base check "now dont frighten me".

opening the throttle rather than closing it is not unheard of, in the same way getting left and right mixed up.

2 events spring to mind
bma viscount at manchester, fo put a bootful of the wrong rudder in and put the a/c on its back during an assymetric exercise.

a student opened the throttle and went into go around on first solo instead of closing it for touchdown, clever chap as well chairman of hp bulmer!

whatunion says i never get confused, i think!