..err.. How exactly do you...?

[sp0nge]

This may sound a little stoopid but I am pretty keen to find the answer. :doh:

 

How exactly do you go about switching a fighter jet on? :music_whistling:

 

Is there like an ignition switch, or a key? :P

 

:huh:

[Snowcat]

http://en.wikipedia.org/wiki/Jet_engine

 

This link should help you out just scroll down & you will find the relevent patr you are looking for

[sp0nge]

I'm not entirely sure I understood all that.

 

So they do it from outside the a/c?

 

I understand how they ignite it, and how it works.. (kinda) but Im more after how the pilot would switch on them from within the cockpit, if he, in actual fact does do this :smartass:

 

http://en.wikipedia.org/wiki/Jet_engine

 

This link should help you out just scroll down & you will find the relevent patr you are looking for

 

[Snowcat]

If I remember correctly they an External Power Unit to start the engine. All the pilot has to do is flick a few switches (so to speak b4 I get flamed)LOL!! But there ppl on these forums far more qualified to answer this question than me, I just did a Google search & found that.

[Fjordmonkey]

It depends on the type of jet. The F-16, for one, can be started without any outside input at all through the Jet Fuel Starter (JFS). The JFS is simply put a small, one-stage jet engine with about 220hp that is started before the main engine. The JFS itself is started through a hydraulic starter-system which is fed by two large reservoirs between the ventral fins. It uses 3000psi hyd-pressure straigh from the two bottles. Can also mention that the two bottles will be the first to be replenished when the engine is up and running. They're also used in the event of a flameout and airstart in the air, although I think at that point that Start1 is used just so that you have two tries to relight. If that doesn't work, you're in trouble :P

 

Here's a quick and very basic breakdown of the startup-procedure that's used for the Norwegian F-16's. Mind you, it's been 7 years since I worked on the Vipers, so I MIGHT remember things somewhat wrong.

 

1: Pilot sets main power to BATT through switch in the cockpit, throttle is checked and set to CUTOFF. Groundcrew signal that they're go for startup.

 

2: JFS-switch is pulled into START 2 (Uses both bottles to start, even though the TCTO states that Start 1 can be used. Due to Norways rather harsh temps at times, START2 is always used, winter as summer. Trust me, it's a bitch to manually pump the JFS bottle-pressure up to 3000psi, and Start2 lessens the possibility of a miss-start)

 

3: 2 small doors on the left side of the aircraft open up. The forward one is the intake for the JFS, the second one is the exhaust. JFS spins up within a few seconds.

 

4: Approximately 7 to 10 seconds after Start 2 has been flipped, the JFS is at full RPM and is turning the Airframe-mounted gearbox (generators, hydpumps etch is attached to this, if memory serves me). Through that gearbox, the engine-mounted gearbox start to turn, and thus also the engine itself.

 

5: At approximately 20 to 25% indicated engine RPM, the throttle is advanced to IDLE which also triggers ignition. Main engine is spooling up (with a deep, almost cow-like sound that will make everything vibrate). JFS Shutdown occures at around 40% rpm, the JFS-doors close, at around 45% engine RPM, the engine is lit and will sustain itself, stabilizing between 65 and 68% RPM (IDLE). At that point, external lights will come on, and the ground-crew is clear to move in.

 

After that there's a ton of tests, alignments and checks that will be done, EXCEPT when the aircraft is at RS15 (Ready Station 15). At that point all we did was pretty much crank it up, yank the pins, run out of the shelter so that the pilot could do an EPU Bleed-air test (you don't want to be anywhere near the aircraft if the EPU fires, since it runs on Hydrazine H70, which again is highly toxic). The aircraft taxis out, we pull the weapon-pins and the Chaff/Flare-pin, hold them up so that the pilot can see them, and off he goes. I sat on RS15 when Kursk sank, and let's just say that it's an insane adrenaline-rush to get woken up at 2am by a claxon and then having to run like a madmad down into the shelter. Just wish it wasn't because of such tragic events :/

 

I also recommend you watching this vid, since it deals with the startup of an F16 seen from the cockpit. It's from a Greek viper, so there are some small differences in procedures.

 

http://video.google.com/videoplay?docid=-3995150967736597998&q=%22f-16%22

 

Older aircraft, for example the F104 and F5, used a small cart that contain a one-stage jet-engine that supplied high-pressure air into the engines to turn them over and start them. The F16 has this option, but it's rarely, if ever, used due to it being time-consuming and can be dangerous due to the proximity to the air-intake. If you get sucked into the intake of an F16, it's byebye-time. You WILL not survive, unlike the guy that got sucked into the intake of an A6 aboard a carrier.

[britgliderpilot]

Also suggest watching the Ka50 cold start video that was released a while ago.

 

They may be turboshafts rather than turbofans, but the start principle is pretty much the same.

[Groove]

I like the SR-71 startup procedure most ^^

 

 

Lockheed SR-71/J58 AG330 Start Cart

 

The AG330 start cart was developed exclusively for the Lockheed SR-71's Pratt & Whitney J58 turbojet engines. The cart used two Buick Wildcat V-8 racing engines, each of 425 cubic inch displacement. Together the engines produced over 600 horsepower and were tied to a common gear box to deliver torque through the starter drive shaft to the J-58s. The aircraft engines had to be run up to at least 3,200 rpm for ignition.

[VMFA-Blaze]

Two Buick Wildcat 425 cu. in engines that's from the mussel car days .... :thumbsup:

Nice find.....

 

~S~

 

 

Blaze

[ZoomBoy27]

Shift-L and then RWIN-HOME

[sp0nge]

Thanks for the responses guys.

 

It was really cuttin' me up .

[RogueRunner]

Of course there is a few things to look out for like enough battery power to avoid a hotstart, wind direction on some turbines (B206 engine for example), also to avoid a hotstart and N1 RPM before you introduce fuel. Hotstarts are very very expensive little mishaps :D :D