intake

Hello people, just after a "approx" figure for the 777 APU burn on the ground when under load. Any reference from the manuals would be great too! Thanks intake....

leewan

Abt 150 - 100 kgs per hour depending on whether the packs are off.

Straight & Level

According to the MEL, the APU uses 240 KG/HR on the ground and 90 KG/HR in the air plus an additional 2.5% onto the trip fuel to account for the open APU air inlet door.

The QRH details this increment from 140 KG/HR at 43,000' and 140 Tons Gross weight to 270 KG/HR at 5,000' and 300 Tons Gross weight. The heavier the aircraft, and the lower the altitude, the higher the burn. The QRH values include the APU fuel flow and the effect of the increased drag from the APU door.

Hope that helps!