GD&L,
...but an airplane on single engine above MLW has to come down quicker than normal, to keep a smooth descent gradient, right...
Depends on the phase of flight. During the descent, more or less standard speeds will be flown (unless during driftdown). For final approach, you are correct in as much as at a higher weight, you need a higher Vref and hence a higher Rate of Descent to maintain a 3 degree slope. Ultimately you have to flare a little higher in theory. In practice, unless you're somewhere extreme, the RoD will only be different by 100fpm or so. Vref is also dependent on your flap setting, which may be different depending on the performance available for the go-around. Hot, high and heavy, for example, you are likely to be forced to use Flap 20 (say) rather than having the choice of that or your normal landing setting. Obviously this is type dependent, I can only speak for the 777.
And the assymetric landing due to fuel imbalance, is it possible?
Not entirely sure what you mean? The only way a fuel imbalance in itself could cause an assymetric landing is if the respective tank has run dry and the appropriate crossflow valves are stuck closed. Pretty unlikely to occur in fact.
In this case, the engine ran down (possibly due to a gearbox failure). Clearly then, this engine will not use the fuel from it's own tank. Not sure about 767 specifics, but there would come a point where a "fuel imbalance checklist" would be used, however the imbalance can often be considerable (several tons) before this is necessary. Different types have different limitations in terms of imbalance. Provided you stay within these limits, the handling won't be compromised.
Hope this helps.
Well done chaps.
