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Old 30th May 2010, 22:43
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john_tullamarine
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Training must have really gone down hill. We were required to keep it tracking on runway leading (and 767 runway track) especially during rotation and establishing V2 to V2 + 10. If not we remained for training.

And, for routine failures (high gross weight, V1 .. the normal sort of sim thing) such is a walk in the park and just about any pilot can produce the required goods.

However,

(a) going back to some Australian DCA studies with a major domestic carrier many years ago in the sim ... for an unexpected failure, the reality was that a significant minority of pilots performed far worse with respect to tracking integrity than when they were primed for the failure .. and this for "easy" failure conditions

(b) some years ago I did a stint of contract work in the 732 sim for an operator which routinely flew (and trained for) high overspeed schedules. However, this operator also had at least one airport from which it routinely flew a short range positioning flight .. at min weight and min speed schedule .. but with no exposure in the sim.

I thought it might be interesting to see how folk fared with some increased difficulty (all in an appropriate, relaxed and friendly manner). The results I found very interesting. Even the more experienced checkies etc., had some difficulty until they'd had a couple of goes to get the gyrations under control.

As a note, this operator had modelled a large bird takeoff engine impact from the FDR and the sim responses appeared to be quite realistic to me .. sitting in the backseat, as I was, watching on ...

As we were doing a lot of initial command training (generally from 744 FO) I decided to spend some of the spare time in getting these guys and gals up to a higher than routine standard. In general, it took a very solid session (with absolute max use of freeze and reset) to move progressively back from the failure comfort zone and get to the stage where a min speed, min schedule, aft CG, worst failure (available on the box) situation (with the failure occuring during the early part of the rotation flare) could be handled with skill, dexterity and considerable aplomb .. including tracking out on the opposite end localiser .. indeed the folk could handle the situation without going to FSD during the failure .. which is pretty good in my view.

All good fun, lots of sweating in the front .. and the kids went home on a cloud of swelled head and confidence .. and slept that night like babies.

Might I be so impertinent as to suggest that you might ask to look at that sort of scenario in your next sim. Unless the sim setup is very benign in that corner of the envelope .. it is interesting.

Some examples? Any in the U.S. Airports where 737 type aircraft operate?

Can't speak to the US.

Several come to mind in Australia (CBR, HBA, for instance). Doesn't really matter .. just one is enough to defeat the philosophy you are espousing as a Standards consideration.

If I am lined up to go and the altimeter setting drops 1 mb, am I covered? My company uses a 2 mb tolerance for reduced thrust TO, but is there a required tolerance for Max Thrust TO calcualtions?

Generally we incorporate some calculation fat for pressure variations otherwise the Regulators might look at us over thick-rimmed school ma'am glasses during the audit ...

In practical terms, the effect for small Hp variations is pretty small. If you don't have any specific guidance then, presuming you do have some general chart information, say WAT limits, you can figure a notional reduce rate in terms of kg/100ft, say, and apply that for mum and the kids when looking up the RTOW data. The result will be pretty close to the sort of figure you might get by running the calculations with a minor difference in Hp input.

So a reported 10kt headwind is calculated as if the real headwind were 5kts, and a reported 10kt tailwind calculated as if the real tailwind were 15kts.

As a sideline note, if you have graphical data available, you can see this effect on the wind grid (if tabular, you might have to plot the graph yourself) in that the slope of the lines (as W/C varies) changes at zero wind .. the effect is small for light weights/distances but quite noticeable at the other end of the envelope.
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