Posted on 08/27/2018 1:11:54 PM PDT by blu
In short, what you have said about “wet starts” is they are not caused by pilots “hot dogging” but are a simple failure of the fuel mixture to ignite during an intended and proper attempt to start the engines. Something that would only occur when the plane is on the line and ready for takeoff not when they are waiting in positions on the perimeter of the deck with engines pointing away from the deck towards the sea.
Correct terminology notwithstanding, is that about right?
And that was just in flight school...
It has been many years, but I think the process has not changed much...
Think of the inside of the engine as a huge gas stove. There are combustion cans arranged radially around the engine just in front of the turbine. The engine I worked on had ten of those cans each can is open in the front for air to come in and open at the back to eject hot gasses of jet combustion.
Inside each “Can” is a fuel nozzle which sprays aerosolized jet fuel into the can. Compressed air comes in one end of the can, fuel is injected, it burns, and hot gasses exit the aft end of the combustion can, hitting the turbine, spinning it (which drives the compressor section in front of the cans) and the remaining power of the thrust not eaten up by the turbine is ejected out the tailpipe as thrust.
One of the cans has a great big huge spark plug in it which is about the size of the tip of your fingers to the crook of your elbow. This is used to “light off” the engine when starting. And it emits a great big huge nasty spark to ignite the fuel mixture. (I know this because I removed a spark igniter once without grounding it first per instructions, and I nearly got a concussion from slamming my head against the inside of the plane when that spark nailed me)
Anyway, IIRC, when starting the plane, you begin pushing air from a huffer through the engine, and when a certain number of RPM is hit, you bring the throttle forward to idle, and immediately push the throttle outboard to initiate the great big huge spark igniter.
When you shove the throttle forward to idle (or start, I cannot remember if the two are the same) it turns on the fuel control which begins spraying the fuel into the cans.
When you immediately shove the throttle outboard, that big spark igniter kicks off, begins sparking in that one can and lights the fuel on fire.
Then, just like a gas stove, the flame spreads from can to can, igniting each one in turn until all are lit.
The Exhaust Gas Temperature (EGT, measured by a thermocouple right behind the turbine) goes up, levels off, and the RPM rises to idle, the pilot brings the throttle back inboard, the great big huge spark plug stops sparking, and the engine is now self-sustaining.
If the spark plug does not spark (Bad electronics, bad capacitor, bad wiring, bad spark igniter, bad throttle linkage etc.) the spark doesn’t occur, no light-off happens, and raw fuel comes out the back of the tailpipe in a big cloud.
Sometimes the issue is with the fuel control (not enough fuel delivered) or the actual fuel itself (may be contaminated) and sometimes the issue is even with the fuel nozzle, though that is rare.
Sometimes the huffer is defective, and not enough air gets pushed through.
In all these cases, you can end up with a wet start.
Now, a hot start can tack right onto the back of a wet start...let’s say the pilot shoves the throttle forward, then outboard to light off the engine, but for some reason the throttle doesn’t go far enough or something, and then just at the point where the temp should be rising but isn’t and the plane captain is signalling to abort the start, the pilot really shoves the throttle outbound and the connection is made to the igniter...then you can have a big ball of flame shoot out the back, the EGT will rise (sometimes dangerously) and the engine is either shut back down or...a stubborn pilot just lets it burn out and stay lit. You try to avoid that because it is bad for the turbine and other things)
Again, this is all from memory some forty years ago, but...I think I remember it all correctly!
There...now you can go take the exam for your A&P License!
Honestly, itsahoot, we can criticize McCain justly for a lot of things.
IMO, This one is a bad choice to do it on.
I would suggest just letting this go. All it does is give the people who wish to marginalize us a valid excuse to do so.
He had three accidents:
Pancaked in flying an AD1 Skyraider (Spad) (his fault,lost track of his altitude)
Ran into wires flying too low in another Spad (his fault too by his own admission, hotdogging)
Finally had an engine failure in a T-2 Buckeye and ejected.(an investigation found no evidence of an engine failure, but they did fault his handing of the engine failure before he ejected)
Then of course, his plane was destroyed on the Forrestal through no fault of his, and he was shot down in another plane, which...happens.
Hence the “Ace” designation.
I should amend that lengthy reply to state that an intentional wet start may be manually induced by a pilot simply bringing the throttle up to the start/idle position, but not engaging the spark igniter.
People talk about pilots playing pranks and doing it and such, but not only did I never see it done intentionally, ever on a land base, I can tell you with 100% certainty that no pilot even a stupid one, a bad one or a rogue one would do it intentionally on the deck of an aircraft carrier.
Never. Ever.
There is too much opportunity for injury, death and destruction and even the dimmest of bulbs understand that.
Wasn't a missile it was a Zuni, a rocket, it came from an F-4.
totally devoid of documentation.
It is a fact Jack, watch the vid.
ping
LOL
OK, I am set for the test. Now where do I go to get the nerve to stand on a flight deck!?!
Yep.
Probably, but you are likely the only one that read it.
Read what? Not sure I understand.
My comment that you commented on. If you hadn't noticed FR is not the same as it was 20 years ago.
Checkmate.
I wasn’t here 20 years ago, that is true. I’m not the same person I was twenty years ago, and the world certainly isn’t the same either.
I did read your comment...I don’t agree with the sentiment if I understand the drift correctly, but I am not here to tell people what to think (as if I had the power to do that anyway)
Just engaging in discourse is all. I think it can still happen on Free Republic, even if many of us often comment without reading the article...and I did read the article too, in this case.
I just got done last night ripping a new one of someone on social media for labeling the converse of that statement the absolute truth...something which originated with the 0bama supporters in the ‘08 election. I decided to search FR to see if anyone else here chose to parrot the false claims. Though there are others, you stand out with your response.
With your counterstatement you are supporting 0bama supporters and promoting lies which make the rest of us look bad. I researched this accident extensively in high school >30 years ago and revisited it a number of times over the years; CPB’s comment is demonstrably more accurate than your lefty-parroted blather.
I believe all the Forrestal accident conspiracy theorists should be lumped together with all the 9/11 conspiracy-theorists and called out.
Right now you’re the king. Congratulations, king idiot.
Spot-on.
I was in a knockdown conflict last night on social media with another alleged Conservative promoting that 0bama-era BS originating from his supporters in ‘08.
People which promote the lies should be labeled no different than the 9/11 truthers.
It’s demonstrably stupid to assert any of the BS about McCain firing a missile into his own plane or his engine lighting off a rocket off-axis on the F4 on the aft deck.
They’re not “nerds”; I’m a nerd. They’re in the same class as 9/11 truthers, Jesters at best.
FReepers spreading those lies parroting the ‘08 propaganda are no better than the 9/11 truthers, IMHO.
I see he didn’t reply to you, but I’ll bet $1000 he didn’t look at the links.
I’m thinking one of these idiots is the guy I flamed last night on social media on this topic.
“Funny” indeed.
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