Learjet destroyed during engine runs?

[LJ45]

I yield to you because you have experience with the aircraft. So I don't doubt what you are saying to be true.

This is of course getting off topic from the original post, but I would be interested in a brief breakdown of how this pseudo fadec/deec works? The reason I ask, we had DEECs on the Westwind, but it was basically just full throttle and it would set your t/o power. Worked much much better than the EECs.

So I assume on the Lear 45 series, It is like having a 1 channel FADEC, but it's a DEEC because it has mechanical backup and not dual channel?

EDIT: Well I should say it has 1 channel electrical, and then mechanical backup. As where FADEC is dual channel electrical, no mechanical backup, and thus if both channels fail, no turbine turning

So it's like a hybrid in a since. Would this be a proper way to describe it?

Thanks for the knowledge!

you got it! Hybrid system is a good description.

 

[b707guy]

Sounds kinda fishy, that or the techs didn't know what they were doing. If you lose power lever control over the engine (DEEC) you can always push the FIRE button which closes the fuel SOV. I've heard of power lever jams and DEEC malfunctions but never an inability to shut down the engine. Sounds like whatever happened they panicked and forgot about the buttons.

Just an observer here with no knowledge of Lears or their systems. Where are the fire SOVs physically located in relation to normal fuel SOV (if they are different valves, that is)? My experience with other aircraft in using the fire SOV instead of the normal fuel shutoff to shut down an engine is that it takes anywhere from 15 seconds at high power to over a minute at idle for the engine to actually shut down, due to the amount of fuel in the lines downstream of the fire SOV. Just curious.

 

[LJ45]

good point, the SOV's for the fuel are located at the wing.

 

[SDCFI]

good point, the SOV's for the fuel are located at the wing.

Funny, the Pilot Training Guide calls them Firewall Shutoff Valves but they're actually in the wing.

If you're thinking fast you could always push the Fire Buttons and blow the bottles, that'll stop 'em in a hurry!

 

[LJ45]

Funny, the Pilot Training Guide calls them Firewall Shutoff Valves but they're actually in the wing.

If you're thinking fast you could always push the Fire Buttons and blow the bottles, that'll stop 'em in a hurry!

really... how will the fire bottles stop them in a hurry, you might want to take that back before you get slammed on flightinfo. :erm:

Some of the valves are at, or near the firewall