PPRuNe Forums - View Single Post - Jet goes down on its way to Medellin, Colombia
Old 8th Dec 2016, 08:17
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sabenaboy
 
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I find this additional info recently added on avherald.com very interesting. It shows that even without payload they would have been approximately 1450 kg short of a legal blocks fuel to perform the flight. I think it's pretty sure that they departed very much above Max TOW. Even with optimistic weights being used, there would have been less fuel in the tanks then the required trip fuel!
Originally Posted by avherald.com
Fuel Computations

A dispatcher at a large airline together with input from The Aviation Herald computed various flight plan possibilities with respect to distances and fuel needed according to Bolivia's law. During the accident flight the enroute winds averaged at a headwind component of 4 knots.

In summary it can be said, that flights from Santa Cruz (VVI) to Medellin (MDE) or Bogota (BOG) could not have been planned legally, even if the aircraft was equipped with pannier tanks. Even in optimistic computations the computed trip fuel alone, without any taxi, contingency, diversion or reserve fuel, would have exceeded the standard fuel tank capacity (9362kg).

The dispatcher computed three different flight plans, see in detail at the PDF:

Santa Cruz-Medellin Alternate Bogota with no payload: Trip Fuel 8,660kg, Release Fuel 11,838kg
Santa Cruz-Medellin Alternate Bogota optimistic weights: Trip Fuel 9,380kg, Release Fuel 12,461kg
Santa Cruz-Bogota Alternate Medellin optimistic weights: Trip Fuel 9,260kg, Release Fuel 12,578kg

Fuel Stop Possibilities

Along the route following possibilities were checked with respect of a possible fuel stop (rounded Great Circle distances used for first leg to fuel stop and second leg to Medellin):

- Cobija (Bolivia, SLCO, 500nm+1100nm): operating from sunrise to sunset only, not open anymore at estimated time of arrival
- Tabatinga (Brazil, SBTT, 900nm+700nm): Brazil did not permit flights from Brazil to Colombia for the Bolivia registered operator, in addition the aerodrome and fuel facilities would have been closed after 23:00Z
- Leticia (Colombia, SKLT, 900nm+700nm): The airport would be open 24/7, fuel services however officially only available until 00:30Z, too tight for estimated arrival
- Bogota (Colombia, SKBO, 1500nm+100nm): as seen above not legally possible

Summary: provided an arrangement with the fuel services in Leticia could have been reached, so that refuelling would have been possible after usual service hours, Leticia would have been an ideal fuel stop.

Last edited by sabenaboy; 8th Dec 2016 at 08:59.
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