Flying overhead shuts down the engines

[v2tec]

When I am flying overhead a while (a few seconds) the whole systems shuts down and I have to restart the engines.

 

Is that a normal A10 behaviour?

Is there anything I have to switch off to avoid this or is it just not possible to fly overhead for a longer time?

 

Is there a chance to fast restart the engines or do I have to load the APU... etc.

[ilikepie]

if you mean inverted (upside down) then yes that's normal as its a gravity feed fuel system.

 

rtm on in-flight engine restarts. as the wiki has a few in valid links in it.

Edited November 17, 2012 by ilikepie
coffee

[PFunk1606688187]

I believe the manual says that the A-10 has fuel collectors that are able to sustain full throttle in negative G flight for 10 or 12 seconds.

 

Longest you wanna stay inverted is for a couple seconds coming out of a half cuban 8, make sure you have good airspeed and your pipper is on or beneath ( appears above when inverted) the target and kick the airplane around 180 on its roll axis.

 

If you have enough altitude you can do a windwill restart, but one engine is more than enough to sustain level flight which should allow you to boot up the APU in order to restart your other engine. If both engines are gone may be in trouble, but windmill still applies, but low alt pretty much requires either fast fast APU start on one engine or an emergency landing.

[v2tec]

I see, thx.

[sobek]

if you mean inverted (upside down) then yes that's normal as its a gravity feed fuel system.

 

No it's not, there are fuel pumps, it's just that the fuel lines run dry.

[Faelwolf]

I'm rather curious as to why they did not put in a fuel system that allows inverted flight, they've been around since WW-II. Anyone know if there is a reason behind this?

[Rusty_M]

It would probably cost a lot more to implement and produce a fuel system which could allow for sustained inverted flight. A cost that probably can't be justified for an aircraft that doesn't really need to sustain negative G for a long time. For the most part, negative G is more awkward than positive anyway.

[ilikepie]

No it's not, there are fuel pumps, it's just that the fuel lines run dry.

 

thanks for clarifying. :book:

[Dejjvid]

Without having a clue about the A-10 fuel system, i believe that there's only a fuel pickup in the bottom of the tanks. If the engineers wanted prolonged inverted flight to be possible they could easily add another set of pickups in the top of the tanks.

 

Instead they installed catch tanks that feed your engines while you're inverted.

[PFunk1606688187]

It would probably cost a lot more to implement and produce a fuel system which could allow for sustained inverted flight.

 

Forget cost, its probably about maintenance. The more systems you add the more difficult it is to fix and or track down a problem and the more parts you need on the fly.

 

Like was already said, fuel collectors allow inverted flight at max thrust for around 10 or 12 seconds, more than enough time to complete your Half Cuban 8 which is mostly performed with strong back stick pressure leading at positive G loads through most of the maneuver meaning even then you're not experiencing Negative G for any longer than you remain inverted before the roll back to normal attitude.

 

A-10 was never meant to fly upside down and doesn't really have a need to. Think about it, all that ground fire coming at you and you're going to put the titanium bath tub AWAY from it?

 

Naw, just one more thing to worry about at improvised forward airbases (a core principle in the simplicity of the A-10s design).

[arteedecco]

I reminded myself of the limited inverted flight time while showboating upside down... only to end up flaming out both engines... managed to get the APU going and then re-light one engine, which provided enough thrust to keep me off the ground. The issue is... I don't have split throttle and didn't remember how to idle one engine, so to restart... you have to set throttle to idle during startup sequence. So... I had to pull both throttles back to idle while engine 2 restarted, once again brushing the bottom of the jet off the ground. I think I saw 30 feet on the radar altimeter twice, but did manage to get it done! FTW!

 

What is it again... "the burned hand learns best..." :)

[doright]

I'm rather curious as to why they did not put in a fuel system that allows inverted flight, they've been around since WW-II. Anyone know if there is a reason behind this?

 

I think you'll find very, very few aircraft are capable of sustained inverted flight. In addition to fuel starvation the engine oil has similar pick up problems or the oil could not flow to or pool in places and causes problems. Not to mention for the pilot it is extremely uncomfortable.

[Sierra99]

No it's not, there are fuel pumps, it's just that the fuel lines run dry.

 

 

Silly thing is... the engines are below the fuel tanks when the aircraft is inverted...

[sobek]

Silly thing is... the engines are below the fuel tanks when the aircraft is inverted...

 

So? :)

[PFunk1606688187]

There just isn't much of a good reason to be flying upside down if you aren't pulling positive Gs, meaning you're still changing your flight vector as a product of a maneuver.

 

The only real reason to need sustained inverted G flying, other than to pull off a Top Gun Polaroid, is for professional aerobatics which incorporate lots of absurd maneuvers, such as totally inverted negative G loops and cubans.

 

Now, fuel injection and boost pumps are pretty important. I remember the first time I flew one of those Hurricane Mk. 1s in IL-2 1946 and much to my dismay any negative G just shut the entire engine down.

 

A-10 is comparatively hard to starve out. :P