Hello fellow MD-11 drivers!

 

Today I was flying a 6.5 hour UPS MD-11 flight from EDDK (Cologne) > UAAA (Almaty).

 

While in the Ural mountains in Southern Russia, I got a "Fuel Temp Lo" warning, while at FL360. I did nothing about this, and left the PC for a while................

 

........ When I returned, my speed had dropped from Mach 0.825 to Mach 0.69, and when I checked my engine instruments, Engines 1 and 3 had cut out !!! ........ (Engine 2 still running fine). The fuel temperature was extremely low on engines 1 and 3.

 

I descended to FL240, where the "Fuel Temp Lo" warning went out, and engines 1 and 3 were successfully started on the first attempt, and the flight was resumed, with a safe landing in Almaty.

 

Awesome! ..... what a simulation this is !!!!!!

 

....but my question is, in the absensce of any type of fuel heating system, what is the correct action to take on getting a 'fuel temp lo' warning, in order to avoid what happened here?

 

Is it just to descend as soon as the warning comes?

 

I take it Engine Anti Ice is nothing to do with this warning?

 

Thanks,

Raul Hernandez

There aren't any fuel heaters on that aircraft?

Engine anti-ice removes ice from your engine cowlings, it doesn't affect your fuel system.

 

Have you checked the QRH for the right procedure?

In any case you want to get warmer air flowing over your wings, so your best option is indeed to descend (lower = warmer). IRL flying faster will also help (more friction => warmer wings), but I don't know how well FS models this.

In any case you want to get warmer air flowing over your wings, so your best option is indeed to descend (lower = warmer). IRL flying faster will also help (more friction => warmer wings), but I don't know how well FS models this.

 

Yes, descending resolved the issue on this occasion. Interesting to hear about the increasing of speed - I will certainly try this the next time; I was at 0.825, so could try increasing to 0.84 to see if that resolved the warnings.

 

Would be interesting to hear from anyone who knows the real QRH actions to take in this instance.

 

Thanks.

There aren't any fuel heaters on that aircraft?

 

No. The fuel system will transfer fuel between tanks 1 and 3 (and the tail tank if there is fuel in it) to warm up the fuel. If it can't warm the fuel, you will need to descend to a warmer altitude. If you don't the engines may fail.

 

In any case you want to get warmer air flowing over your wings, so your best option is indeed to descend (lower = warmer). IRL flying faster will also help (more friction => warmer wings), but I don't know how well FS models this.

 

I don't know if FSX will do that, but that is real-world procedure.

 

real QRH actions to take in this instance.

 

That is the QRH procedure. Descend and increase speed.

 

To avoid this, you can load different types of fuel via the INIT page 3. See the FMS Preflight section of the FMS manual (or the Intro manual; can't remember at the moment) for different types of fuel.

 

I take it Engine Anti Ice is nothing to do with this warning?

 

Correct.

left the PC for a while

 

With PMDG products, you need to keep an eye on the aircraft. I think this would constitute at least negligence in the real life bird. Though it is not always possible in our computer world (which may be a good thing).

Well as you touched upon, in the sim world, it is not always possible to be in front of the PC for 6.5 hours without a break .......... certainly not when you have 3 young children lol!

 

Where possible I try to simulate reality, but this was a case where the PC had to be left for a moment while I picked the kids up from school :wink:

View Postjapascoe, on 30 November 2012 - 06:33 PM, said:

In any case you want to get warmer air flowing over your wings, so your best option is indeed to descend (lower = warmer). IRL flying faster will also help (more friction => warmer wings), but I don't know how well FS models this.

 

I don't know if FSX will do that, but that is real-world procedure.

 

Increasing airspeed will warm up the fuel in FS (at least on the comlpex addons) Fuel temp is linked to TAT and will slowly match it.

In the fms you can change the fuel type to a winter blend which has a much lower gel temp than regular jet a1, i believe its jet a5 but its been awhile since ive flown my md over a route that gets cold enough. But when i do i change that fuel as part of my preflight

In the fms you can change the fuel type to a winter blend which has a much lower gel temp than regular jet a1, i believe its jet a5 but its been awhile since ive flown my md over a route that gets cold enough. But when i do i change that fuel as part of my preflight

 

Ahhhh..... I did not know this! ... Thank you... :smile: .... I will take a look at that. It seems this is the preventative measure for this issue, as I have been getting a lot of fuel temp low warnings in the Northern Hemisphere lately.

Awesome! ..... what a simulation this is !!!!!!

 

Hi Raul,

 

may I direct your attention to the thread http://forum.avsim.n...n-fuel-temp-lo/ ?

 

I had the same experience a couple of weeks ago.

 

The root cause for the low temperatur is that I purchased the OPUS weather machine which lacks a proper winds/temperature aloft injection. Instead they somehow interpolate the data they have to cruising altitutes, obviously not so well.... 8^( The aloft patch is announced (without date).

 

Consequently I fallback after TOC to the FSX weather (for this you have to stop/terminate the OPUS window -- it is not enough to switch to 15mn cycle download, as OPUS takes over control after the set time interval or distance). Shortly before TOD I switch OPUS on again in order to enjoy the better lower altitude weather.

 

Have fun!

 

There aren't any fuel heaters on that aircraft?

 

The original aircraft lets the fuel circulate. The belly tank 2 is warmer than the wing tanks.

 

The sim at least saves the tail tank fuel forward... Amazing.

The three fuel types are Jet A (-40 °C), Jet A1 (-47 °C) and Jet B (-50 °C), but Jet B is incorrect in the sim - it should have a freezing point of -60 °C, and is designed for use in very cold climates.

 

If you want to be more realistic, use Jet A1 when flying out of Europe - Jet A is only available in the US, and is not used in Europe as it is a lower grade fuel (not so good).

 

Best regards,

Robin.

Hi Raul,

 

may I direct your attention to the thread http://forum.avsim.n...n-fuel-temp-lo/ ?

 

I had the same experience a couple of weeks ago.

 

The root cause for the low temperatur is that I purchased the OPUS weather machine which lacks a proper winds/temperature aloft injection. Instead they somehow interpolate the data they have to cruising altitutes, obviously not so well.... 8^( The aloft patch is announced (without date).

 

Consequently I fallback after TOC to the FSX weather (for this you have to stop/terminate the OPUS window -- it is not enough to switch to 15mn cycle download, as OPUS takes over control after the set time interval or distance). Shortly before TOD I switch OPUS on again in order to enjoy the better lower altitude weather.

 

Have fun!

 

 

 

The original aircraft lets the fuel circulate. The belly tank 2 is warmer than the wing tanks.

 

The sim at least saves the tail tank fuel forward... Amazing.

 

Ah! ..... Thank you, you are exactly right - theses "fuel temp lo" warnings are happening since I bought OPUS. I never quite realised that that was the case but yes, 100%.

 

Thanks. :smile: ... I will also look at the fuel type suggestion too.

 

The original aircraft lets the fuel circulate. The belly tank 2 is warmer than the wing tanks.

 

The sim at least saves the tail tank fuel forward... Amazing.

 

Had I read the whole post before I replied I never would have asked. ;-)