I'd like to ask pilots familiar with similar airplanes to the MD82 to comment on the questions below. Please allow me to make a few premises:
-Flaps and slats were properly set for TO. Perhaps flaps setting was a bit smaller than it should've been due to miscalculation or some malfunction, but not much. Say they were a couple of degrees shorter than they should've been. They were symetrical.
-Engines (and engine fuel supply systems) don't fail for the duration of the TO.
-Weather and other conditions were like in the accident, except that actual real ones were understimated by 2% (i.e. wind was tail 9kt+2%, airplane weight was 64.263+2%, air temperature was 30º+2%)
-Reversers didn't deploy uncommanded for the duration of the maneuver.
What on earth could make such a plane take some 500m longer than it should to complete V1+rotation, and then roll left-right heavily while entering stall-like condition?
Again, this is not to fuel "speculation". It's just an attempt on my side to learn better how airplanes work and some of the actions involved in take-offs.
Of course replies such as: "on those conditions, it's virtually impossible to produce such an accident" are perfectly acceptable. I just wanna know if there is anything anyone can think of that would fit the picture.
Of course, on-air collision with something, wind shear or major control functions failure could also precipitate the airplane to the ground, but wouldn't likely explain the long roll/rotation time.
Would something like ailerons stuck in "up" position be something necessarily noticed by crew before reaching V1?
If flaps/slats were deployed say "late" in the TO maneuver (say close to V1 the pilot realizes the mistake and lowers them), and by the time they reach VR they are deployed ... then surely, as long as enough thrust is produced, there shouldn't have been any stall, right?
Also, some witnesses refer to the nose angle during rotation as "weird".
Could a cargo piece such as that 400kg refrigerated container have moved and create enough imbalance to "throw off" the nose angle to the extend of being so steep to produce stall but still have the tail not hit the ground? I'm guessing not, but then again I haven't touched a flight simulator in 20 years and have never piloted any kind of airplane.
Again, OBVIOUSLY I don't know what I'm talking about, but I would certainly appreciate for those that do know to please explain a bit what, if anything, they can think of scenarios like these.
And also,
-About how many seconds does it usually take for these planes to reach flaps 15º/slats down from 0 setting?
-If you are flying with the bare minimun V2 and thrust setting to mantain it, and you extend flaps "suddently" from 0 to 15 and activate slats (no thrrust increase)... would the drag lower the speed and produce a stall condition?
-How responsive are the engines in this airplane on 30º air? I.e. about roughly how many seconds it would take them to increase thrust from say 70% to 80%?
Sorry for asking so many questions and thank for bearing with me. I'm trying to get a better picture on how much margin for errors or problems there are in these types of planes during take-off.
TIA.