737 APU start failure suggestion
We are getting more and more APU faults during starts...typically around one in twenty five starts.
Never happens on the first sector.... almost exclusively happens when OAT is 25 degrees C or over. BITE Fault indication is invariably "slow acceleration".
Engineers advise it is a problem which occurs with our type of APU as it gets older. Advice is to start it when cold. Typically around 5000'...sure enough they start every time at altitude.
Apart from the 5 mins plus of extra fuel can anybody see any technical issues with starting APUs between 10,000 and 5,000'?
I know the problem needs fixing...but in the mean time I am not over keen on using air start carts three times a month if it can be avoided by an early APU start.