Cf6-80c2 relight envelope
 

The qrh for my aircraft only specifies a minimum N2 for a windmill relight,does anybody have a diagram of airspeed and altitude to achieve this figure? I am guessing about 300kt up to FL 300 but would be interested in figures for lower altitudes.

Your performance manual or FCOM should have an envelope.

The FCOM just states for a windmill start below FL 300.

Can't find one for a -80C2.

This is for a CF6-80E1.

http://i39.tinypic.com/2u4tx6w.jpg


And for a CF6-50C2

http://i41.tinypic.com/mcrx21.jpg

Min n2 relight is the fuel on command bug. Represents 15 of n2. Max inflight re engagement of n2 is 30 or u will damage the gearbox
Max on ground is 1% change of n2 in 5 secs

What about HOT Relights - ie within 10 seconds of flame out. If you are quick enough you should be able to get those flames going again at max altitude. Some fighters have auto relighters.

The EEC has auto relight as installed in the 744, too. Igniters are lit automatically if N2 goes below idle.

QRH sez use the Start switch below 220 KIAS and N2 <20% if the EEC doesn't catch it.

Thank you for the info. The CF6 I had in mind only has a pmc and no autorelight.