TIGHAR

Amelia Earhart Search Forum => Alternate Lines of Inquiry => Topic started by: Colin Taylor on March 19, 2023, 03:30:06 PM

Title: Drift in the Dark part 2
Post by: Colin Taylor on March 19, 2023, 03:30:06 PM
Drift in the Dark part 2

How much fuel on board was available for the flight?

 The original fuel capacity of the Electra comprised 13 tanks totalling 1198 USG. This was later reduced to 12 tanks total 1151 USG. At Lae the tanks were filled with 80 octane gasoline, presumably to the brim, in the absence of fuel gauges for the extra tanks. One tank was part-full of 100 octane fuel for extra power at take-off. This was not topped off, leaving the fuel load approximately 50 USG short. Total fuel was therefore approximately 1100 USG.

How much fuel was un-useable?

 The weight of all the fuel has to be counted for the Take-Off Weight of the aircraft but not all of the fuel is useable because of the shape of the tanks and the arrangement of pick-ups, pipe-work and valves.  With 12 tanks, maybe 12 USG was un-useable. There were four fuel selectors and a cross-feed valve, so that the system required very careful management. Using all of the fuel would require running each tank dry and switching tanks when the fuel pressure dropped or the engine stopped; and you have to know which tank to select next, that still has fuel.
 
How much fuel is used for taxi and take-off?
 
 At idle the fuel consumption is very low but during take-off at full throttle and maximum rich mixture the fuel consumption is significantly greater than at cruise power settings. I have allocated 5 USG for taxi and take-off.
Why take-off at 10:00am L (local time) at Lae (00:00 GMT)? (Greenwich Mean Time)?
 Take-off should not be too late because of the need to avoid high air temperature and thunderstorms after midday at Lae. Also, not too early because of Sunrise at Howland at 05:45 L Howland (17:15 GMT). The expected flight time was 18hrs 49 mins and arrival time 18:49 GMT.