Reasons why the engine won't turn over

[tbaac]

I bought this plane at the weekend. Nice detail to it. (and COTS).

I'm having trouble starting the engines. Starting from Cold&Dark, I try going through the checklists and when I get to priming the first engine (3) and then pressing Start, nothing seems to happen. I don't hear the engine turning over. I have the Master switches on, Battery on and DC voltage is shown (19V or so). (I've also tried turning on the fuel, generator and mags but that isn't needed for turning the engine over as I understand it).

When I use Ctrl+E the engines start and I can hear them turn over prior to firing. When I use Shift+8 the engines are in Excellent condition.

Can you think of anything that I might not have turned on?

Thanks.

[Scott - A2A]

Make sure your Masters and battery are on, and you have used your Engine Selector to select an engine.

Scott.

[tbaac]

Thanks Scott. It seems odd. I tried a shorter checklist and it worked.

Do you know approximately what the minimum bus voltage is below which an engine can't be started?

Thanks again,

[Jacques]

With your APU on you shouldn't need to worry about running your batteries down. I did pour through all the literature I have collected, and searched online, but came up empty handed. I will keep looking, though. Which checklist did you use before that didn't work?

JP


Sent from my iPad using Tapatalk

[tbaac]

Thanks Jacques. I used a checklist based on the ones in the B377 Pilot's Manual that comes with the plane but it definitely included the parts of the checklist that Scott mentioned
(I rearranged it so that there was more done at a single station before moving on and so that the engineer worked in one part of the panel before moving to the next bit etc. This didn't seem to matter too much because if the battery, master switches and avionics are off then the order won't be that important I guess.)

I wasn't sure about the APU. I was using it but it seemed like it was different from the APU in a 737 for example. There, a little engine runs to provide power. Here the APU just seems to produce a power boost, possibly at the expense of battery life.

I tried attaching my checklists as a file but .txt wasn't allowed as an extension apparently.

Thanks again.

[Medtner]

I made the mistake the first time that I had the APU on "run" and not "a.p.p". The distinction seems to be basically "start" and "connect". If not switched over to "a.p.p" the APU will not do any work for you.

[tbaac]

That's interesting and could explain it, thanks Erik. You may have solved my problem

Can anyone tell me out of interesting what the APU consisted of on a 377? Did one switch start up a little engine?
Thanks.

[dacamp66]

Direct quote from the COTS manual
"An on-board APU provides electrical power while engines are off, and also for engine starting. The APU drives a 28-volt, 500-ampere,direct current generator which is also used as a starting motor. The APU will operate to altitudes of 20,000 feet with generator output of 14 kilowatts at 28 volt DC. At altitudes under 10,000 feet, the generator can provide a five minute supply of 17.4 kilowatts at 28 volt DC (approximately 620 amp). Fuel is supplied from the tank No. 2 or from the fuel manifold and is automatically shut off whenever the APU is not operating. The APU has a self-contained oil supply. An air intake duct allows air to flow to the turbine compressor, while an
exhaust duct provides means for exhausting products of combustion. A valve in each duct is connected by a rod and linkage to operate together (open or close) from a manual control handle next to APU. The handle is spring-loaded to the OPEN or to the CLOSED position to prevent valve gates from creeping. The intake duct valve actuates a micro-switch in the control circuit to prevent APU operation with the intake and exhaust ducts closed.The APU can also be used as a standby electrical power source for takeoff and landing, or as an emergency power source during flights up to 20,000 feet (cabin must be de-pressurized). A blower is installed in the airplane to pressurize the turbine compartment.

The turbine compartment is pressurized to prevent exhaust fumes from entering the control cabin. The blower also aids in cooling the APU compartment. The blower is operable in flight or on the ground. The APU generator will continuously deliver 500 amps."
looks like it was a heavy duty generator much like what is used by homeowners today as an emergency power source.

[tbaac]

Oh, thanks for that

I've been concentrating on reading the pilot's manual and obviously missed that in the COTS manual. (I haven't tried using COTS yet).

Plus I've no attention span. I'll try this for a bit then go back to the P51 before remembering that the Spit is so nice. (and then I'll go back to a flight in the C172......)

[Neon]

Also on the APU, it's a small diesel engine if I remember rightly.

Welcome to the beautiful world of the B377.

[Tailspin45]

Again, from the manual, "Fuel is supplied from the tank No. 2 or from the fuel manifold and is automatically shut off whenever the APU is not operating." IOW it runs on gasoline.