Hccmclown:
Why on earth would a pilot leave an engine running due to an APU starter issue "in case they couldn't get a start"? This statement does not make sense at all.
And anyone in the industry would refer to the starter as a Garrett, not an Airresearch.
You are displaying your ignorance yet again and obviously not a pilot or an engineer.
1. The RR Spey engines in an F28 at the time have air starters like most jets. They need compressed air which is supplied by the APU, GPU or a rather large ground based large air tank to start. Once one engine is started, it can provide bleed air to start the other one.
2. At the outstations in far Northern Western Australia there was no GPU or GSE. If both engines are shut down as is the usual practice, then you are reliant on the APU for starting, and if that won't start you are stuffed.
3. The APU's were built by Garrett Airesearch as it was then called. The provider of the biggest heap of shyte in the aviation industry and I'm paraphrasing old Jim Blue who told us that at a Boeing conference in Seattle.
The particular problem with this heap of crap of an APU involved the starter - an electric motor that spun the thing up to about 10% N1 (say 10,000 rpm) for ignition. The starter was then supposed to disengage via the aforesaid sprag clutch so that the motor didn't spin up to 100% N1 along with the APU turbine.
...And the things often didn't disengage - which meant the armature "grew until it hit the case and failed...... and the next time the pilot shut down and tried to restart via the APU.....she no start. We stuck in Karratha until an engineer arrives with a new starter.
Sorry for being verbose, but you did ask. After some sixty starter failures and associated delays, the F28 pilots decided to keep the Port engine running at idle at outstations rather than risk another failure and delay. Airesearch took forever to redesign the starter clutch.
As I said, failure of the gear to retract is only a minor issue after you are safely back on the ground with the gear pinned.