i am no professional pilot but:
if the right reverser would have deployed during take off run don't you think the crew would have realized that the plane drifts extremely to the right ?
There is one known case where the crew had no indication whatsoever that they dealt with a #2 reverser deployment under similar circumstances, in an aircraft with a relatively comparable geometry, a Fokker 100, TAM Flt. 402, Oct. 31, 1996:
YouTube - TAM 402 de 1996 com legenda - transcrição caixa preta + FDR
Fokkerpilot.net - TAM 402 - CVR/FDR video. A must see!
What follows is a narrative of flt. 402:
Quote:
TAM flight 402 was a regular flight between São Paulo (CGH) and Rio de Janeiro (SDU). At 08:25 the flight received clearance for takeoff
from runway 17R. Wind was given as 060 degrees. At 08:26:00 the throttles were advanced for takeoff power. Ten seconds later a double beep was heard. The captain said "O auto-throttle tá fora" and the copilot adjusted the throttles manually and informed the captain: "thrust check". With this information he confirmed that the take-off power had been adjusted and verified. Ar 08:26:19 the airplane accelerated through 80 kts. At 08:26:32 the copilot indicated "V one". Two seconds later the airplane rotated at a speed of 131 kts. At 08:26:36 the air/ground switch transited from "ground" "to "air". The speed was 136 kts and the airplane was climbing at an angle of 10 degrees. At that same moment a shock was felt and the EPR of engine nr. 2 dropped from 1.69 to 1.34, indicating the loss of power. In fact, the nr.2 engine thrust reverser had deployed. An eye witness confirmed to have seen at least two complete cycles of opening and closing of the nr.2 thrust reverser buckets during the flight. The loss of power on the right side caused the plane to roll to the right. The captain applied left rudder and left aileron to counteract the movement of the plane. The copilot advanced both thrust levers, but they retarted again almost immediately,
causing the power of the nr.1 engine to drop to 1.328 EPR and engine nr. 2 to 1,133 EPR. Both crew members were preoccupied by the movement of the throttles and did not know that the thrust reverser on the nr.2 engine had deployed. The throttles were forced forward again.
At 08:26:44 the captain ordered the autothrottle to be disengaged. One second later the nr.2 thrust lever retarted again and remained at idle for two seconds. The airspeed fell to 126 kts. At 08:26:48 the copilot announced that he had disengaged the autothrottles. He then jammed the nr. 2 thrust lever fully forward again. Both engines now reached 1,724 EPR. With the thrust reverser deployed, the airspeed declined at 2kts per second. At 08:26:55 the stick shaker activated, warning of an impeding stall. The airplane rolled to a 39 degree bank angle and the GPWS activated: "Don't sink!". Seven secons later the airplane impacted building and crashed into a heavily populated neighborhood."
Unquote
And this is the source:
ASN Aircraft accident Fokker 100 PT-MRK São Paulo, SP
Apparently there was no drift to the right until the aircraft became airborne. And please notice the flight control inputs in the simulation (based on CVR and FDR data) in an attempt to compensate for the yaw to the right. There are procedures in place on the Fo100 in case of a thrust reverser unlock situation, which can be managed if a reverser unlock light is presented. This crew (TAM 402) unfortunately did not receive any indications and were fighting the engaged AT before finally disengaging it. By then it was too late. Perhaps this crew never realized they were fighting a deployed #2 reverser because until the very end the copilot jammed the #2 thrust lever fully forward. . . . . .
Again, there is as yet no conclusive evidence this scenario fits the Spanair MD82, but it cannot be ruled out either until the facts are known.
Regards,
Green-dot