marciovp
You have to be familiar with the concept of DDG or "Dispatch Deviation Guide", from which the already mentioned MEL "Minimum Equipment List" is derived : Due to the built-in redundancies in an aircraft an equipment could be inoperative without impairing the safety of its operations. You then have, after some serious statistic computations a decision on the airworthiness of this said aircraft, the faulty item is either a *no GO* or a MELed item of which there are several classes of period - be it in airframe hours or a number of sectors or a number of days before which the failure is fixed. Items are classified as A,B,C or D in order of decreasing importance.
Furthermore, each MELed item comes with a maintenance procedure ( here the locking of the reverser and the verification that the EEC / FADEC has recognised the inoperability of the reverser ), a crew procedure (here the use of
both T/Ls ) and a dispatch limitation (Ops on contaminated runways forbidden, for instance ).
The final decision on the aircraft dispatch with one - or more - MELed systems on the ATL is the Captain's.
Why ten days ? First of all it is the maximum period the aircraft is allowed to fly with this defect. Unless the DGCA authorizes for special reasons the extension of the period (the aircraft unable to return to base in time, for instance), the aircraft is grounded until repair is made. As the T/R is not, in most cases, required in normal good weather operations, ten days it is .
PJ2
In aviation, a designer has every right to expect a level of competence and specialized, intensive training and even directs it when airlines/corporations buy their products. It is a proven fact that where training falls well short of these goals, accidents are going to happen
My sentiment, entirely.