Maintenance
I knew that the possibility of maintenance will come up. Before I get shot and killed by the pprune police (No not the moderators) I want to say that I am in no way trying to guess the reason or reasons leading to or contributing to this accident. I am more than happy to wait for a report. However I would like to comment maintenance in general.
Airlines are forced to comply by rules and regulations set forth by the manufacturer of the aircraft, component or part or their respective CAA/FAA. Many companies find it cheaper in the short term to reduce the maintenance burden by performing the absolute minimum required to keep an aircraft flying. The older the aircraft more maintenance is needed to keep it in the air. Not just any kind of maintenance but a specific type that seems to be done less and less: Preventive Maintenance and associated Trend Monitoring.
Trend monitoring of individual components such as an engine will show the deterioration of performance and should prompt an engine change before a catastophic failure occurs. Many companies will tend to fly their engines to TBO limit or until the performance reaches unacceptable values. This saves money in the short term but how about in the long term?
An engine failure in one of the more obscure places in the world requiring a landing back an engine change and the downtime with a possible charter to move the time critical cargo can run into the millions. What is the cost of having engineers work on aircraft during the downtime and perform old fashioned preventive maintenance, certainly less than the scenario above. The older and the more complex or the larger the aircraft is, the more care it requires. This places a huge burden on shoestring operations where cost of operating the aircraft and revenue are virtually the same. One factor in the equation increases and the company will start to lose money. Solution is to save somewhere else. While the savings make perfect sense to the book keepers operationally they might be totally wrong.
MEL has become the Holy cow of an operation. One needs to ask several questions before accepting an aircraft with deferred maintenance items DMI or equivalent. Is it OK by MEL to go? Is it smart even if the MEL allows to go and how do multiple DMI's interact and affect the aircraft operation. One DMI item might be ok, but if you have several and it is still legal to go, operating according to normal procedures can become extremely difficult.
Again I must say that the above post does not judge or guess the reasons leading to the 2nd Kallitta accident rather is my 2 pence worth on the maintenance brought up by other contributors to this thread.