All in all take-off performance is not one-dimensional ..
.. of course, until one comes to the Board of Inquiry/Coronial/Royal Commission/whatever ... when the legal folks will make it very much so. Not a problem, I guess, provided that one has a good story and that story is based soundly on certification and operating regulation ?
even when I was flying it was very unusual to hit a VMCG limit.
Indeed. Most pilots rarely come across the problem which is one reason for its not figuring much in the accident record. Minimum weight, minimum speed schedules is where one might see the problem, depending on Type characteristics.
In part, this was exacerbated by the old UK certification requirements which set VMCG some 10KT higher than FARs and JARs would do.
For most who might be confused by this statement, the old BCARs figured Vmcg for a 7kt crosswind (if my memory serves me correctly) while everyone else uses nil wind. I would expect that the delta should vary depending on number of engines etc.
I would be surprised if an airline would schedule any aircraft certificated under JARS or FARs into a VMCG limited field
An interesting point of view. I think it more likely that such will be of little concern to the commercial driver .. if the aircraft is able to get in/out and the aerodrome meets the various aerodrome standards then, guess what ?
they certainly would not do it without providing clear guidance to the crew.
It is on this point that many operators fall down miserably. Removing all reference to specific Vmcg data is a salient example
Interesting is the boeing issued training material for narrow runway operation which adresses VMCg concerns, especially in the combination of narrow runway and crosswind.
I can't recall reviewing the Boeing presentation(s) but I'm certainly not surprised. The practical limit on runway width generally comes out to be the Vmcg centreline deviation figures under whatever conditions might be built into the operating (as opposed to certification) rules.
It is pertinent that line folks should be aware that crosswind has a VERY real effect on the book Vmcg for the day's takeoff. Typical rules of thumb vary from 0.5kt/kt increase for twins up to something in excess of 1kt/kt for quads. Now, if one happens to be in the (very bad hair day) situation of having a near Vmcg schedule, with a significant crosswind, and one loses one on the "wrong" side, then one is highly likely to have a close encounter of the grass filled kind ....