- #1
Andre
- 4,311
- 74
Let's do an exercise in safetly management and sound judgement.
In some countries somebody is considered guilty if there is an accident with casualties. Maybe we could do a little court marshalling to find out who is guilty in the following mishap, It pertains a take off crash of some Air Force jet of the type ‘Voodoo’ (F-101) way back in the 1950's.
I read about it years ago and tried to find it back on internet, but googling failed. So no links, just from how I recall it.
The jet started the take off roll and accelerated as per normal but it never got airborne. Eventually the pilot was trying to bring the aircraft to a stop at the last moment, by deploying the drag chute. I can’t recall if it had a tail hook and if the runway had an arrester cable installed, but anyhow, all failed and the aircraft departed the end of the runway at high speed and dipped into a stream where it came to a full stop. The pilot attempted to exit the cockpit but the canopy was jammed due to the deformation in the crash and most unfortunately he drowned before the rescue party could free him.
The safety board was riddled initially, every piece of the aircraft was fully functional until impact, there was only one fishy thing, which made it possible to find the most probable cause. I summarize the elements that played a role in the development of the mishap in chronological order:
1. There was a major exercise ongoing on the air base, that got all priorities
2. The mishap aircraft was to be flown to a commercial airfield where it would go to a civil contractor for a modification.
3. The aircraft contained a secret aiming device that had to be removed prior to it going to the industry.
4. A specialist went to the aircraft to remove that gadget but when he actually had the apparatus in his hands pulling it out the avionics bay, he was called away for a high priority repair on another aircraft to be ready for the exercise. It was the shouting now-drop everything-immediate type of call.
5. Eventually he returned to the aircraft to finish up, close up the access doors and collect the tools.
6. The crew chief responsible for the aircraft, prepared it for the flight next. He was highly regarded, a real can-do person, he realized the stress the technician was in, when he did that job and decided to check if everything was done correctly. However, in doing so, he discovered that there was still an open tube in that avionics bay. It was an air tube of the pitot static system, which is the main input for the pneumatic airspeed indicator. This is where the gadget had been connected to, since it also needed the dynamic/ram air pressure input. The technician should have plugged that during that job he did.
7. As there was quite a bit of time pressure, and he could not find a dedicated plug for that hole nor could he recall the technician, the crew chief decided to repair it himself provisionally. This was not unusual; actually it was is known as ‘battle damage repair’ and he took some duct tape and closed off the hole.
8. A young inexperienced pilot had to do the transition flight to the civil airfield. This was not standard procedure, but all the experienced pilots were occupied in the exercise.
Those are the bare facts leading to the accident which was deducted to be as follows:
As the jet was accelerating on the runway, the dynamic air pressure building up in the tube, for the airspeed indicater, started to leak away along the duct tape, as it was not sealed air tight. The reduced pressure caused the airspeed indicator to indicate a lower value than the real speed.
Most likely, the pilot had no idea what was going on and waited with the rotation for flight for the airspeed to hit the rotation-take off speed mark. But this never came, so he finally aborted the take off attempt, but obviously too late.
So, who was ultimately responsible for the death of the pilot?
A: The technician, who did not do a proper job and who left that hole open?
B: The crewchief for a non standard repair job?
C: The pilot for the inability to judge that the airspeed outside and inside were mismatching?
D: The management of the air base for, mixing routine maintenance jobs with the high priority exercise?
E: The aircraft manufacturer for not providing an emergency exit possibility in case of a jammed canopy.
Obviously, there is no canned preset good answer. It’s just about your judgement, why somebody is to blame. It would also be interesting to learn about your recommendation to prevent this kind of mishaps in the future.
In some countries somebody is considered guilty if there is an accident with casualties. Maybe we could do a little court marshalling to find out who is guilty in the following mishap, It pertains a take off crash of some Air Force jet of the type ‘Voodoo’ (F-101) way back in the 1950's.
I read about it years ago and tried to find it back on internet, but googling failed. So no links, just from how I recall it.
The jet started the take off roll and accelerated as per normal but it never got airborne. Eventually the pilot was trying to bring the aircraft to a stop at the last moment, by deploying the drag chute. I can’t recall if it had a tail hook and if the runway had an arrester cable installed, but anyhow, all failed and the aircraft departed the end of the runway at high speed and dipped into a stream where it came to a full stop. The pilot attempted to exit the cockpit but the canopy was jammed due to the deformation in the crash and most unfortunately he drowned before the rescue party could free him.
The safety board was riddled initially, every piece of the aircraft was fully functional until impact, there was only one fishy thing, which made it possible to find the most probable cause. I summarize the elements that played a role in the development of the mishap in chronological order:
1. There was a major exercise ongoing on the air base, that got all priorities
2. The mishap aircraft was to be flown to a commercial airfield where it would go to a civil contractor for a modification.
3. The aircraft contained a secret aiming device that had to be removed prior to it going to the industry.
4. A specialist went to the aircraft to remove that gadget but when he actually had the apparatus in his hands pulling it out the avionics bay, he was called away for a high priority repair on another aircraft to be ready for the exercise. It was the shouting now-drop everything-immediate type of call.
5. Eventually he returned to the aircraft to finish up, close up the access doors and collect the tools.
6. The crew chief responsible for the aircraft, prepared it for the flight next. He was highly regarded, a real can-do person, he realized the stress the technician was in, when he did that job and decided to check if everything was done correctly. However, in doing so, he discovered that there was still an open tube in that avionics bay. It was an air tube of the pitot static system, which is the main input for the pneumatic airspeed indicator. This is where the gadget had been connected to, since it also needed the dynamic/ram air pressure input. The technician should have plugged that during that job he did.
7. As there was quite a bit of time pressure, and he could not find a dedicated plug for that hole nor could he recall the technician, the crew chief decided to repair it himself provisionally. This was not unusual; actually it was is known as ‘battle damage repair’ and he took some duct tape and closed off the hole.
8. A young inexperienced pilot had to do the transition flight to the civil airfield. This was not standard procedure, but all the experienced pilots were occupied in the exercise.
Those are the bare facts leading to the accident which was deducted to be as follows:
As the jet was accelerating on the runway, the dynamic air pressure building up in the tube, for the airspeed indicater, started to leak away along the duct tape, as it was not sealed air tight. The reduced pressure caused the airspeed indicator to indicate a lower value than the real speed.
Most likely, the pilot had no idea what was going on and waited with the rotation for flight for the airspeed to hit the rotation-take off speed mark. But this never came, so he finally aborted the take off attempt, but obviously too late.
So, who was ultimately responsible for the death of the pilot?
A: The technician, who did not do a proper job and who left that hole open?
B: The crewchief for a non standard repair job?
C: The pilot for the inability to judge that the airspeed outside and inside were mismatching?
D: The management of the air base for, mixing routine maintenance jobs with the high priority exercise?
E: The aircraft manufacturer for not providing an emergency exit possibility in case of a jammed canopy.
Obviously, there is no canned preset good answer. It’s just about your judgement, why somebody is to blame. It would also be interesting to learn about your recommendation to prevent this kind of mishaps in the future.