RB211s starting

[lomapaseo]

Please enlighten us as to the OEM limits for the abnormal start you are referring to.

If I had such a start I would be extremely concerned and abort the start well before idle.

This is a windup surely.

I like the play on words "this is a windup surely"

One of the reasons that you may not get the fan turning during start is that the blade tips have managed to windmill backwards jamming the tips into their fan case. The start sequence turns the non fan compressor rotor and its only the air from this rotor flowing through the aft turbine that begins to add torque to spin the fan. Until the engine actually stabilizes at idle the rotors are not well matched in RPM differences (not a biggie since you aren't expecting much power).

The key to a good start is what the EGT is telling you (burner stabilization) and the engine reaching a stabilzed (at idle) match between spool RPMs.

On the other hand if there are any concerns they would be stated in the FCOMs etc. by the manufacturer

Perhaps there is a corralary somwhere in the turboprop world of starting vs the prop speed

[TURIN]

With your experiece and knowledge concerning turbofan and turbojet engines i doubt you would put your hands anywhere near N1 stage unless any source of bleed air was unavailable.

You are right Capt Inop, however on a live aircraft full of passengers the APU will be running and the packs doing all they can to keep them happy.
The luxury of isolating the engines/start valve etc is often not available when slots are at a premium and the station manager is standing behind you impatiently tapping his/her foot.

It is the way of the new world unfortunately.

[spannersatcx]

station manager is standing behind you impatiently tapping his/her foot.

Just ignore them, I do!

[Old Fella]

Smoke on start

The RB211 series DO NOT NORMALLY exhibit such volumes of smoke on start. It seems obvious to me that these engines had been inhibited for long term storage and that they had not been started in quite a while. Normally fuel is introduced at either Max motoring RPM or 25% N3. It was also not clear if only No 3 was being started in the video clip. If so, the start was probably slower than usual due to pressure loss (APU output) because of the distance of the APU from No 3 Engine. L1011 APU's were not particularly efficient at best.

[rudderrudderrat]

More smoke on start

Hi Old Fella,

I agree. Even a brand new Trent will smoke as the preservative oil is burned off.
787-first-trent
"ZA001 started its Rolls-Royce Trent 1000 engines for the first time. White smoke was seen coming from the engine as storage oil was burnt off as the engines were spooled up."

[411A]

The RB211 series DO NOT NORMALLY exhibit such volumes of smoke on start.

I have to smile when I see these statements.

What it should read is...'do not normally exhibit such volumes of smoke, unless the ambient temperature at the airfield is quite low, and the engine has been cold soaked.'
Very common to see these engines smoke on startup, under the above scenario.
In addition, also under these circumstances, a wing engine will normally spool up faster, during start.
The proximity of the number two engine to the APU is immaterial.

[lomapaseo]

What it should read is...'do not normally exhibit such volumes of smoke, unless the ambient temperature at the airfield is quite low, and the engine has been cold soaked.'
Very common to see these engines smoke on startup, under the above scenario.
In addition, also under these circumstances, a wing engine will normally spool up faster, during start.
The proximity of the number two engine to the APU is immaterial.

Come to think of it, that is the only time I have seen RB211 engines on L1011's smoke on start up. Does give credence to the labryinth seal theory though.

We still don't have a confirmation from what it smells like (fuel or oil) from somebody standing directly behind one though

[ZQA297/30]

I used to operate L-1011s from the Caribbean to LHR, where the aircraft turned around in about 2 hrs. No smoke on summertime starts at LHR, but every once in a while when it was really cold at LHR,there would be a cloud of smoke that smelled strongly of kerosene. Noticed it with other operators too. Also operated to YYZ where it was colder, but not as many "smokers". Beats me!

[grounded27]

We still don't have a confirmation from what it smells like (fuel or oil) from somebody standing directly behind one though

Have no doubt it is fuel, it is there when it is warm out as well, just in more of a gasious form thus transparent.

[Old Fella]

Smiling 411A

Pleased you were able to smile 411A. I also have operated L1011 and RB211 powered B747's in very cold conditions (Kimpo in mid-winter as well as Narita, Osaka etc). I have never witnessed that amount of smoke on start from any engine regardless of ambient conditions. The engine start shown on the YouTube clip took almost 3 minutes to stabilize at idle, inordinately long and smoking for about two minutes hence my DO NOT NORMALLY statement. I also would debate your claim that a wing engine, if started in isolation using only APU bleed air, will spool up quicker than No 2.

[VR-HFX]

411

I'm with Old Fella. Never seen this amount of smoke on the 1011 even on the coldest Kimpo mornings, but then I only have about 8K on type.

Neither did I see it on the 742/3 Classic we operated.

This must have been an engine that had been corked for quite a while.

[411A]

The 'smokers' were nearly always -22B engines, the -524 series hardly ever 'smoked' in my sixteen thousand hours on type.

I also would debate your claim that a wing engine, if started in isolation using only APU bleed air, will spool up quicker than No 2.

Debate aside, that has been my experience.
Normally, old time Flight Engineers have wanted to place a small wager on the point...I prevailed every time, using the clock.
Imagine that, they actually learned something from the Commander...

[Old Fella]

Learning from Commanders

411A I have learnt much from Commanders over the years and am happy to admit it. Equally some Commanders have at times, they tell me, benefitted from my advice. I also stand by my assertion re time to stabilize No 2 engine v's a Wing Engine during starting using only APU bleed air. I would suspect that you have "suckered" in those against whom you wagered by using Engine x-bleed from an operating engine when starting a wing engine. Other than that I can see no reason why a wing mounted engine should start any quicker than No2 and I do believe that the proximity of No 2 engine to the APU does have an effect on available air to the starter.

[barit1]

To be clear, I have (almost) no experience on the type.

But an episode at Haneda 26 years ago is very vivid in my memory. I was to ride jump seat in a newly-delivered All Nippon 747SR, and was lounging in the upper deck waiting for a gaggle of NH techs to complete their cockpit orientation tour.

I heard a foghorn-like sound begin, which I thought was some hydraulic noise. I tried to deduce what the trainees were doing to make such a sound - until I happened to glance outside. 500m down the ramp a 1011 was emitting a fog from #2 - just like the Roswell video. It took at least 2 min. for the fog generator to cease, at which time the foghorn also stopped.

[barit1]

lomapaseo (re locked-rotor starting):

Perhaps there is a corralary somwhere in the turboprop world of starting vs the prop speed

The 2-spool turboprops/turboshafts I'm familiar with are all approved for locked-rotor starts. VH-3D Marine One is an example, with core engines running but the helo rotor braked to a halt when el presidente embarks/disembarks.

And the CT7 turboprop has an extra pad on the prop gearbox for mounting a disc brake - but I don't know if any customers have ordered this option.

[411A]

I would suspect that you have "suckered" in those against whom you wagered by using Engine x-bleed from an operating engine when starting a wing engine.

Oh come now, Old Fella this is quite likely impossible, as...the engine bleed controls are within reach of the Flight Engineer, and...if these same folks were actually paying attention (Yes I know, sometimes a stretch), I'm quite sure they would have noticed that another engine was operating...

It took at least 2 min. for the fog generator to cease, at which time the foghorn also stopped.

Yup, quite common at times, and yes, even from aircraft that have not been in storage, with engines 'preserved'.

[bcgallacher]

I have also operated RB211 in cold conditions and have seen the clouds of vapour and slow spool up described and agree with 411a (unusually!) as it appears to be 22B engines that suffer from this - never seen it on a 524.

[411A]

...slow spool up described and agree with 411a (unusually!) as it appears to be 22B engines that suffer from this - never seen it on a 524.

Yup, 'tis a fact.

[Old Fella]

Paying attention

Quote: "Flight Engineer, and....if these same folks were paying attention (Yes I know, sometimes a stretch )"

411A, I trust you do not really believe what you post regarding your experience of Flight Engineers. I guess I will just have to leave this topic where it is, agreeing to disagree. One thing we can agree on is that the L1011 would be regarded by most who flew it as being a truly capable aircraft with a great working environment.

[rudderrudderrat]

Hi Old Fella,

L1011 APU's were not particularly efficient at best.

We operated the original -1s and 50s, and the APU was so efficient that we ran an air conditioning pack at the same time as we started the engine (apparently to avoid a pressure surge when the starter motor cut off). I can't remember any significant differences in the starting times between any of the engines.

When using a ground pneumatic starting truck, we'd start the engine closest to the truck (due leaky pressure loss).

Ah - those were the days - I'm envious of 411A.