Originally Posted by
Hot 'n' High
No probs AGBagb, and really sorry if I came across a bit "iffy" - but worth thinking about what designers expect, anticipate what their kit may face and what is, seemingly in this case, one hell of an outlier. And yes, my background is both as an Aerospace Engineer and Commercial Pilot (typical case of "jack of 2 trades - rubbish at both???!!!") hence my take on what is expected/mitigated against in Engineering terms. There will probably be good aero/design reasons to keep some stuff low in the engines - even if just to ensure a good airflow between the top of the engines and the underneath of the wings - don't know as never worked in that field - but I could see that having an effect on say, cruise performance = cost per seat mile! Also, if they'd initiated the go-around before the ground contact, they may not even have realised the ground contact. Timing and the subsequent human filtering and/or delay in processing the sensory input then making a subsequent decision all goes into the mix - that's if they had realised - but sounds like the Capt was past making rational decisions - again, the CVR transcript could help there, as several have pointed out, in how we gain an understanding of the thought processes leading up to Event 1 and the go-around.
Once you make the decision to put the gearbox on the fan case (and as I noted in a post early in this thread, on a CFM sized engine there simply isn't room to mount it on the core as is done on some bigger engines such as the PW4000 and GE90), part of it
has to go at the six o'clock position. The reasons is quite simple - the gearbox drive shaft comes through the lower bifurcation. Putting the gearbox drive anyplace else would require a radical redesign of the entire engine nacelle - throwing away billions of hours of operational experience with the current design practices - and would probably create far more problems than it might solve.