jetcat start problems
 

ok, this started about 2 weeks ago when i was at fentress jets. as always when i started the p-80, the electric motor would spool up, propane would ignite, then a few short seconds later the kero would come online and fire right up. NOW, the past 6 or so starts, the electric motor would spool up propane would ignite, and the electric motor would stop spooling up for a few seconds, almost coming to a complete start, then start to spool back up again and the fire up on the kero,

i am posting this here hoping for a solution, because i want to fly this jet again tomorrow, and jetcat is closed until monday,

any ideas??????

thanks

mark

RE: jetcat start problems
 

It almost sounds like the engine temp is not getting hot enough and the hesitation is waiting for the heat to build before continuing the ramp.
At least thats how we do the manual start on a wren 44.
If your spooling too soon it cools the engine, but if you let it spool down a bit and give the temp a chance to rise, then engage the starter again, the ramp goes off flawlessly.

Im a Jetcat newbie so I'll be interested to see what might be happening.

RE: jetcat start problems
 

Mark, use a leaf blower and blow it in the engine during start up, start soft and go stronger as the start sequence comes along. As long as the electric motor is not sticking to the nut, you'll be good to go till the pros are back in the office.

Sean

RE: jetcat start problems
 

Hi Mark,

Are you sure the propane is igniting on that first cycle? You can check by watching the EGT on the GSU, if the propane lights you will see the temps come up pretty quick. What you are describing usually involves the propane not igniting on the first cycle. If the motor has been starting OK up until now, then the glo plug has gone bad. Or you might be ruuning low on Pwermax.

If it is truly firing up the propane on the first try, then I need to think about it. Is it starting on the second try every time?


Going out for a couple of hours, then I will be back online to help.

Matt

RE: jetcat start problems
 

matt, it fires right up on the propnae, propane is not the problem, ( i think )

there were two of us jet jocks flying today, i compared my start up to his, ( same turbine, p-80)
his electric motor spools up and stays running thru the cycle.

mine starts to spool up, propane fires, the the electric motor stops spooling to almost a dead stop, for about 2 or 3 seconds, then spools back up and fires on the kero,

the p-80 does fire up and run, but it takes longer, much longer to get it up on kero,

now the weather has been very hot and muggy here the past week, 93 today, and humidity very high, so muggy and hazy all day, it looked like we were in the fog, but again, larry fired his up and it ran fine

" puzzled"

RE: jetcat start problems
 

Hi Mark,

This does not sound right. If it was starting OK before, then chances are an adjustment to starting parameters will help. Unfortunately, I do not know what they are right now, I will look into it in the morning.

Regards,

Matt