Engine cutting out at around 17,000 ft

[Davros23]

I have an interesting problem with the Spitfire when climbing. It doesn't happen all the time (happens about 4 times out of 5) but when it does it's quite frustrating. Climbing in various configurations but typically at boost +12, RPM 2850, with second stage supercharger engaged (light on) and IAS between 170 and 190 mph the engine cuts out at around 17,000 ft. Levelling off and reducing the boost to 0 or +2 will get the engine going again. At the point the engine cuts out the radiator temperature will start to fall quite dramatically (to under 60C) and won't recover even after the engine has restarted, until I descend to a lower level. Oil temperature during the climb climbs to around 90C then starts falling slightly when the second stage kicks in.

 

On other occasions, with exactly the same climbing configuration, the aircraft will climb willingly to over 35,000 ft, no problems.

 

Any ideas? To make things more interesting I'm starting to think the problem is more persistent on multiplayer servers so possibly it's an environmental issue?

[philstyle]

Turn on

1 - the fuel pump switch just beneath your elevator trim wheel (left side of cockpit), and

2 - the fuel pressure butterfly valve, above your right foot

[Combat Wombat]

Turn on

1 - the fuel pump switch just beneath your elevator trim wheel (left side of cockpit), and

2 - the fuel pressure butterfly valve, above your right foot

:thumbup:

[Davros23]

Thanks Phil. Note the fuel pressure warning light has not come on so I'm unsure about that. However, the RAF manual says the following -

 

(iii) Use of the booster pump(s)

(a) The main tanks booster pump should be switched ON for

take-off and landing and at all times when these tanks are in use

in flight.

{b) The rear fuselage tanks booster pump should be switched

ON at all times when changing to, or using fuel from, these

tanks.

 

This may therefore have something to do with it, I shall try and see if that helps! Anyone know where the rear booster pump switch is? ;)

[Holbeach]

Thanks Phil. Note the fuel pressure warning light has not come on so I'm unsure about that. However, the RAF manual says the following -

 

(iii) Use of the booster pump(s)

(a) The main tanks booster pump should be switched ON for

take-off and landing and at all times when these tanks are in use

in flight.

{b) The rear fuselage tanks booster pump should be switched

ON at all times when changing to, or using fuel from, these

tanks.

 

This may therefore have something to do with it, I shall try and see if that helps! Anyone know where the rear booster pump switch is? ;)

 

There is no rear tank and therefore no booster for it.

 

Just turn on the main pump only and leave it on.

 

This instruction has been left out of the manual.

 

..

[Davros23]

By the way I'm making an assumption here that the fuel pump switch and the main tanks booster pump are the same thing?

 

I also notice the fuel pump switch is not mentioned operationally in the manual.

[Davros23]

Thanks Holbeach, what I figured.

[Sokol1_br]

(a) The main tanks booster pump should be switched ON for

take-off and landing and at all times when these tanks are in use

in flight.

 

Since there's no way to fly without use tanks, leave ON. :thumbup:

[Whisper]

Since there's no way to fly without use tanks, leave ON. :thumbup:

 

I didn't read carefully (shame on me), but is that true also when using drop tanks?

[Schwarzfeld]

I like to flip every switch inside an airplane to "ON" pretty much any time I climb into an airplane, or an e-plane, as long as the manual doesn't prohibit that prior to startup, and/or that might cause avgas to uh... flow onto the pavement because external tanks aint attached... so, yeah, if it says fuel, leave it on till its time to park and have a beer lol

[ricktoberfest]

I didn't read carefully (shame on me), but is that true also when using drop tanks?

 

 

 

Most aircraft (at least of this era) don't draw directly from wing tanks (as far as I'm aware) but in fact use the wing tanks to constantly fill the main tank until they're empty... so yes leave it on even then.

 

 

Sent from my iPhone using Tapatalk

[Baz JJ]

Vapour lock? Try switching the pressurised fuel tank cock on at altitude ?

 

Normal level was 20,000ft for pressurisation but it might be worth a try at 15,000.

[Spurts]

Love this forum.  I just picked up the Spitfire for trial and went to test the climb performance.  Super happy until the second stage kicked on and had the same issue described in such detail by the OP.  Happy to see it's an easy operational fix.

[mla306]

Agree with Spurts!  I'm having the same problem.  I actually quit playing Big Show and the new Beware campaign because of the same problem.   I thought I read somewhere else on the forum that this was a bug with the spit.  I'll try the fuel pump....hopefully!!!

Thanks for the tips.

[grafspee]

Switch on fuel pump after take off and all problems will be gone

[mla306]

Thanks very much.  Worked great.  Flew Beware mission 2 (I think it was), in good formation, did the climb still in pretty good formation.  Made it over the target area in France.....only to be shot down by a FW190....sigh!  But thanks for the tip....plane worked great!!

[Eclipse]

On 1/18/2023 at 11:41 AM, grafspee said:

Switch on fuel pump after take off and all problems will be gone

It would be great if the fuel pump switch was mentioned in the manual.  They left it out completely, no mention of it anywhere that I've found, besides the cockpit layout with the tag that identifies it as a fuel pump switch.  It should probably be one of the steps in the startup/takeoff sequence... 

But at least now I know why my engine was cutting out at higher altitudes even after switching the fuel pressure valve on once the low fuel pressure light lit up.  

Thanks!

[grafspee]

I was there too, wondering why my spit cutting off at high alt  I think every one went that way in DCS.

Main concern form me, is it true at all, earlier version of spitfires didn't have any electric fuel pumps and they could climb above 17k ft, but somehow our version will but off every time.

I am just ignoring this for now and i turn on fuel pump every time i start spitfire. Start up procedure in spitfire is copy pasted from DCS P-51 so maybe fuel system too, and DCS P-51 fuel system require fuel pump run all the time so DCS spitfire too.

[71st_AH Rob]

Our Spitfire is a bit of a Frankenstein's monster.  Also the real pilot's notes are very confusing, even for many native English speakers, so not surprised that they left it out.  

The wobble pump is from 1942 and early 1943.  The electric pump replaced it in the spring of 1943. 

[grafspee]

9 minutes ago, 71st_AH Rob said:

Our Spitfire is a bit of a Frankenstein's monster.  Also the real pilot's notes are very confusing, even for many native English speakers, so not surprised that they left it out.  

The wobble pump is from 1942 and early 1943.  The electric pump replaced it in the spring of 1943. 

Electric pump in later models but in check list before start you have to operate electric  fuel pump for 30s and the turn it off, because spitfire starts with mixture lever in operation position on the contrary to P-51 which starts with mixture in cut off position. 

[NineGravity]

On 1/24/2017 at 7:49 PM, philstyle said:

Turn on

1 - the fuel pump switch just beneath your elevator trim wheel (left side of cockpit), and

2 - the fuel pressure butterfly valve, above your right foot

Thank you! it works fine now!!!

[Andrimner]

Hello,

I'm having the exact same issue, and while the fuel pump+pressurization resolved some of it, other aspects are still unresolved.

In view of the advice on these forums, I tried switching on both the fuel pump and the pressurization switch as a part of my start-up routine. This led to the engine cutting off shortly after take off EVERY TIME (feeding from drop tank, not sure if that matters). 

So I went back to flying with these switches off, and only switching them on when the engine starts to struggle above 17 000 ft. That worked. 

However, I'm still experiencing unexplainable cut offs, although much later on. This is on the first sortie of the Beware-campaing: I'll typically switch switch on the pump and pressure as we approach 20 000 ft en route to the target, then the drop tank will empty out shortly thereafter, and I'll drop that. Then, the flight encounters german fighters upon returning from the target, and I usually get through the dogfight with the engine intact. HOWEVER, it will cut off on shortly after the dogfight, and I just can't understand why. The first time it happened I obviously overworked the engine, but this time around I kept a close eye on the temperature gauges which were both fine, kept my RPM well under 2 500, constantly checked that the fuel tank was still full. Yet still, as I was throttling up to escape some german fighters, the engine still cut off, with plenty of fuel left, and temperatures well below "danger" levels. 

I just can't understand why this happens. What could be causing my engine to cut off, when there's plenty of fuel left, and all temperatures are within range?

 

[razo+r]

35 minutes ago, Andrimner said:

Hello,

I'm having the exact same issue, and while the fuel pump+pressurization resolved some of it, other aspects are still unresolved.

In view of the advice on these forums, I tried switching on both the fuel pump and the pressurization switch as a part of my start-up routine. This led to the engine cutting off shortly after take off EVERY TIME (feeding from drop tank, not sure if that matters). 

So I went back to flying with these switches off, and only switching them on when the engine starts to struggle above 17 000 ft. That worked. 

However, I'm still experiencing unexplainable cut offs, although much later on. This is on the first sortie of the Beware-campaing: I'll typically switch switch on the pump and pressure as we approach 20 000 ft en route to the target, then the drop tank will empty out shortly thereafter, and I'll drop that. Then, the flight encounters german fighters upon returning from the target, and I usually get through the dogfight with the engine intact. HOWEVER, it will cut off on shortly after the dogfight, and I just can't understand why. The first time it happened I obviously overworked the engine, but this time around I kept a close eye on the temperature gauges which were both fine, kept my RPM well under 2 500, constantly checked that the fuel tank was still full. Yet still, as I was throttling up to escape some german fighters, the engine still cut off, with plenty of fuel left, and temperatures well below "danger" levels. 

I just can't understand why this happens. What could be causing my engine to cut off, when there's plenty of fuel left, and all temperatures are within range?

 

Well, can you tell us what you mean by cut off? Does it sputter and is it still windmilling, or is it a violent bang and instant seizure? 

Depending on which one it is, you can rule out if it's a mechanical failure or something else. 

[PawlaczGMD]

1 hour ago, Andrimner said:

Hello,

I'm having the exact same issue, and while the fuel pump+pressurization resolved some of it, other aspects are still unresolved.

In view of the advice on these forums, I tried switching on both the fuel pump and the pressurization switch as a part of my start-up routine. This led to the engine cutting off shortly after take off EVERY TIME (feeding from drop tank, not sure if that matters). 

So I went back to flying with these switches off, and only switching them on when the engine starts to struggle above 17 000 ft. That worked. 

However, I'm still experiencing unexplainable cut offs, although much later on. This is on the first sortie of the Beware-campaing: I'll typically switch switch on the pump and pressure as we approach 20 000 ft en route to the target, then the drop tank will empty out shortly thereafter, and I'll drop that. Then, the flight encounters german fighters upon returning from the target, and I usually get through the dogfight with the engine intact. HOWEVER, it will cut off on shortly after the dogfight, and I just can't understand why. The first time it happened I obviously overworked the engine, but this time around I kept a close eye on the temperature gauges which were both fine, kept my RPM well under 2 500, constantly checked that the fuel tank was still full. Yet still, as I was throttling up to escape some german fighters, the engine still cut off, with plenty of fuel left, and temperatures well below "danger" levels. 

I just can't understand why this happens. What could be causing my engine to cut off, when there's plenty of fuel left, and all temperatures are within range?

 

What boost are you at? High RPM is not really what damages your engine, high boost at too low RPM is what's bad. At 2500 RPM you should not really exceed 6-7 psi, the manufacturer settings are : 2650 RPM - up to 8 psi, 2850 RPM - up to 12 psi, 3000 RPM - up to 18 psi (5 minutes max). So you want more RPM at high boost, not less.

If your low fuel pressure is not coming on, I would guess that you're just killing the engine by managing it wrong. Including a track of this failure would help diagnose.

[Andrimner]

1 hour ago, razo+r said:

Well, can you tell us what you mean by cut off? Does it sputter and is it still windmilling, or is it a violent bang and instant seizure? 

Depending on which one it is, you can rule out if it's a mechanical failure or something else. 

It sputters, then completely seizes up. Propeller goes totally still

2 minutes ago, PawlaczGMD said:

What boost are you at? High RPM is not really what damages your engine, high boost at too low RPM is what's bad. At 2500 RPM you should not really exceed 6-7 psi, the manufacturer settings are : 2650 RPM - up to 8 psi, 2850 RPM - up to 12 psi, 3000 RPM - up to 18 psi (5 minutes max). So you want more RPM at high boost, not less.

If your low fuel pressure is not coming on, I would guess that you're just killing the engine by managing it wrong. Including a track of this failure would help diagnose.

I make sure to keep boost below 8 during normal flight. In combat I go higher, but the last time, I had turned down pitch until I reached about 2 200 rpm, with a low throttle. Didn't check the boost specifically, but as mentioned, throttle was in the lower half. Then I noticed four german planes which seemed like they were closing, so i maxxed out throttle, and increased pitch to about 2 800 rpm. WIthin seconds, the engine stalled.