There is no requirement for a loadmaster to be on a flight. Once the plane is loaded their job is done. Unless provisions are made for access to the cargo area they can’t get back there in many planes. The exception to this is hazardous material which in some cases requires accessibility during flight.
If you’re doing a one-off charter then the loadmaster needs to get back home and usually will ride back with the plane. If a company is doing multiple charters to the same place then they can keep one loadmaster at that location and have others load the plane from the point of origin.
It’s not a conclusion. That was a preliminary report. From cite below: "But on Monday, Afghan officials cautioned that it was too early to determine the exact cause of the accident, which remains under investigation. "
So where on the runway did they find parts. 'that would answer whether it happened on the roll-out or after rotation. If they had a hard landing and all the freight shifted forward then the straps may have stretched enough to so that a powered brake take off shifted them back enough to stress the tie-down attaching points or strap ends or the straps themselves.
And I wonder what “fractured” with the straps? This source said the straps were “cut” but that could be a language barrier thing or they could have been sheared on impact.
But if the black box was found inside one of the vehicles and the voices were cut off early and parts were found on the runway then that suggests a breakaway of one of the vehicles which sheared through the bulkhead and disconnected the black box. Of course, the plane crashed right at the end of the runway so parts could have been flung back.
If it happened when they let off the brakes at the start of the takeoff roll, then the plane would have looked something like this, and they would never have gotten very far down the runway. Planes are loaded such that the center of mass isn’t very far forward of the main landing gear; that’s the only way the elevator has enough pitch authority to get the nose up off of the ground at 150 knots. Under those circumstances, if 80 tons of cargo shifts to the rear by any significant distance, the plane will pop a wheelie. So it must have happened at/after rotation.
It shouldn’t be difficult to tell where in the cargo area something was at the time of impact. The plane landed basically on its belly. Everything in the cargo area would have left a dent in the floor. A tank that was strapped down would leave a relatively even tread shaped dent. If you find a dent in the floor shaped like a turret or tread sides, you know that tank was loose at the time of impact.
From what I’ve seen, those accident investigators are quite good at identifying how and why any piece of metal failed.
Resurrecting this 8-year-old thread to share a really good video by Mentour Pilot which goes into the details of what happened in this crash:
It’s 24 minutes long, but very interesting. If you’re short on time the highlights are thus:
The plane had actual flown to Bagram with its load of MRAPS aboard.
The loadmaster had used 24 straps on each of the smaller vehicles, and 26 on the larger vehicles; later math by Boeing suggested that 60 straps should have been used on each.
While on layover at Bagram, the cockpit voice recorder captured a crew conversation in which they noted that during the flight to Bagram, the vehicles had shifted enough to produce slack in some straps, and had actually broken one of the taut straps. The loadmaster fixed this by cinching up the slack straps and adding…two more straps.
*At takeoff from Bagram, the rearmost vehicle broke loose (possible others too, but the rearmost one is what matters here) and crashed into the rear pressure dome. It destroyed the jackscrew on the horizontal stabilizer, pushing the stabilizer it to its full pitch-up position. At that point it didn’t matter where the center of mass was for the whole cargo load; there was no way the pilots were going to be able to bring the nose down again.
*That impact of the vehicle on the rear pressure dome also damaged hydraulics, and destroyed the wiring to the black boxes, which are installed in that location; no data or voice was captured after the plane rotated to begin climbing off of the runway.
*One of the final conclusions was that National Cargo hadn’t provided enough oversight/training to its loadmasters. Another was that the FAA hadn’t provided enough oversight over National Cargo.
I saw this a few months ago: The YouTube channel The Flight Channel re-enacts aviation incidents with flight simulators, and gives you a in-the-cockpit view of what was going on. It’s pretty sobering to have that point of view. This Bagram 747 crash is here:
The strap issue reminded me a bit of Richard Feynman’s take on the Challenger loss and how we interpret safety margins. Safety margins are for unexpected fluctuations in loads. If you are counting on them during normal operations, you have no safety margins.
In the case of National Air, the loadmaster and pilots must have felt that since only a couple of straps broke and a couple loosened without anything bad happening that they had enough of a margin of safety holding the load. However, since none of the straps were supposed to fail under normal loading, they had no safety margin at all.
