Please advise on OIL TEMPS
 

I see the T972 ran at about 180C normal cruise.
Max temp allowed is 196C on this engine.

Please advise what your machines run at.
Does not matter what type, or how old or new.
Thank you in advance.

DERG.

I first thought a T972 might be a piston engine or some obscure eastern invention and nearly passed by. Google came up with RR Trent 972.
There are so many abbreviations in aviation, it would help to put a bit more in your post.

My A/C is Airbus A300-B4 and the GE CF6-50C2 normally runs at 80 to 100 C with limits of 160 C continuous and 175 C transient for 15 mins.

Hope this helps.

There is no way on God's earth that I will ever again be invloved with a thread on oil and aircraft. Never.

Thank You! Dixi 188
 

Yes.. indeed I beg your pardon Dixi. Thats exactly the information I was looking for. As far as I was aware before the Qantas/A380 incident that 150C was pretty much tops.

The NTSB has published a preliminary report about the incident and it cleary shows a 180C constant temp on this T972 engine. Further reading revealed a max of 196C. It also has a print out record of "oil chemistry".

My suspicion is that Rolls Royce have robbed cold air from the cooling sysytem to get more thrust out the engine. I am not sure if all these RB211 series engines...they have three main discs with one contra-rotating...run at a higher oil temp then GE-P&W. Are all Rolls Royce engines running at 180C at cruise?

All I am asking here is what is normal oil temp for your aircraft and your engine. Of course there will be locations within the engine where the oil runs at its hottest but the normal guage reading is of interest to me. Thanks for your help.

Not even with a DC-3?? :}

barit1
 

Will you PLEASE stop injecting my threads with your fatuous remarks!
Get the F out of my business and STAY OUT.

DERG

This is an open forum even the thread starter does not own a thread.

I'll delete my response of you'll delete yours :)

DERG The engine will have demonstrated max oil temps etc during endurance testing prior to certification. Cooling will also have been demonstrated to the Regulator's satisfaction.

Are you suggesting that RR have changed the values subsequent to certification?

But before comparing with other engine manufacturers you need to be sure that the temperature is measured at the same place so as to compare apples with apples.

The RB211 535E4 has a max oil temp of 177 deg C, the 524is 100 deg C. But 535 is measured at scavenge return, 524 at outlet from oil pressure pump ie after cooling.

So I am not surprised that oil technology etc has moved on since the 535 so as to be able to cope with a very modest temperature increase.

Oil temperature is specified on the Engine Type Certificate Data Sheets which are easily available online. Well, the CAA ones are, EASA not so easy. FAA probably easy.

Come on, DERG, mine was a friendly poke at c-p, paranthetical to 'your' thread - it should be like water off a duck's back to you. :=

Barit old boy I can barely read enough to type these days so if you have something to add about what you did with that test machine you used to tout around please tell me. That thing must have had some temp guages on it. If not then STFU. What your dad did in WW2 has no bearing on what you did with your career.

Caad Thank you. Of couase I am NOT suggesting RR fraudulently offered false data. They may be incompetent engineers and pass the odd buff envelope around when soliciting business with foreigners....but data fraud NO!

"Oil temperature is specified on the Engine Type Certificate Data Sheets which are easily available online. Well, the CAA ones are, EASA not so easy. FAA probably easy."

Oh really?

The issue is that any oil will begin to vapourise above 150C. This is a valid question of interest and I would be grateful if the more generous members of this forum would tell me what they see on their guages.

One envisions an oiling system that relies on "Aeration" (misting) might contribute to heat induced "Vaporisation?? Coking? There is that "de-aeration" Tray........ One step past "foaming" ?? IMO.

Turbine oil
 

Bear: the foaming happens when oil gets mixed with water either water liquid OR water vapour. Only time it ever foams. I have found my reading spectacles I can now type:ok:

I have yet to encounter any machine that uses oil vapour to achieve lubrication or cooling. I am aware there is a whole new section of science called nanotechnology but I cannot see the oil vapour being used in the technology we are using (publically in civil use) today.

If oil does vapourise it is past it's usefulness and it gives of a flamable gas and leaves a hard carbon residue caled "coking". Bear I know you follow the A-380 thread and it is this gas that upset the computer control of the engine causing the spline wear.

In this thread I am seeking to know what the guys are seeing on their temp guages in day to day operation. No more than that. It may well be that all RR turbines run with the oil around 180C. This adds up when you realise they have THREE turbine sections as opposed to the TWO in GE products.

All repilies very welcome. Barit1 if you can remember what your whirlygig oil temps ran at then please advise.

DERG - If oil vapourises at 150degC, why is the scavenge oil temp of the RB211 535, just about the most reliable gas turbine in existence set at 177degC?

I'm leaving this sideshow now because I prefer a civilised exchange of views. Your views on the integrity of RR are not shared.

Goodbye Caad
 

The 469 passengers on the Qantas 380 that had the explode will also have questions regarding the integrity of Rolls Royce.

The avaition has its fair share of "yes" men unfortunately and probably more than most.

You are no loss Caad.

On the space shuttle we use a special oil that will not boil off at normal temperatures....we have a special indicator as well.....

DERG - Yes, I'm sure I won't be missed, But

WHAT ABOUT THE 535 OIL TEMPERATURE

Sorry to shout, but you really are a bit irritating

Rolls Who?
 

Oil vapourizes above 150C...fact. Prove to me it does not!

Maybe RR units go through a hell of a lot of top oil. No one is counting how many top up tins are poured in because no has to record these additions. Not sure if they even issued the A-380 with an "away pack" to use in top ups.

If oil tecnology had moved on the T970 series would not be in the mess we find it.

Seems to me RR think they are minor deities. They are allowed to product test using the public.

They think they can have THREE turbine discs running and expect the oil to be able to handle a 50% increase in frictional load and temperature.

Moreover they are paranoid about taking bypass air to cool the oil. All in all I get the impression they are in this business cause they always have been. They have leagacy rights to over ride basic physics.

No one is counting how many top up tins are poured in because no has to record these additions.
That's interesting... every freight/public transport aircraft I've worked on had a Tech Log in which all oil/fuel uplifts were recorded.

B757 with RB211-535E4 engines. Cruise oil temps (off the EICAS) are rarely in three digits. They use a little bit of oil, but powerplant engineers monitor uplifts. If it gets excessive, shop visit time.

It is not a fact, it is you talking nonsense.

A standard oil such as Jet Oil II has a flash point of 270°C. If you don't know what flash point means Google it. After 6.5 hours at 204°C, 3% will have been lost through evaporation.

For Jet Oil 254 the evaporation loss is even less.

Mobil Jet Oil II data sheet

You are also talking nonsense when claiming oil replenishment is not recorded. It most certainly is, as anyone who operates or maintains aircraft will know.