B-727 with afterburners?
 

Some years ago I worked for Kuwait Airways on the Jumbo.
They also had a small fleet of B-727s with some kind of afterburner installation/option.
Belive it was -17 engines.
Many 727 guys, instructors and pilots I talked to here in the US have never heard of such a thing.

The 72s were sold to Syria after the Gulf War.
Does anybody out there have more information on the afterburner subject?

Was it automatic power boost in case of eng. failure?
Extra chambers in the tail pipe?
Did Boeing offer them, or after mod from Pratt?
Or what???



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Men, this is no drill...

Don't know about 727's with afterburners,
although some of the models I flew could certainly have used it!

The heavier gross wt versions (up to 210,000lbs) did have the -17R JT8D, with automatic power reserve, that boosted engine
thrust by 1000lbs in the event of an engine
failure.

Interestingly, The MD80 has a similar type system that in addition to boosting the thrust on the other engine, also retracts
the wingtip landing lights, supposed to improve climb by 150fpm!

I remember reading of a Mexican airline that had JATO bottles installed on B727's to help in case of an engine failure from high altitude airports. Could this be the "afterburners" you are referring to?

Are you sure it wasn't the 'hot/high' trident
3bb with the added 5250lb thrust RB162-96 turbojet installed in the tail below the rudder

Uh, no it was B-727 with JT8Ds without no JATO bottles.
It COULD have been some "fuel control unit power boost system", but I think it was a poor man's after burner with raw fuel being pumped into the tail-end of the motor.

Not sure, anybody else heard about it??



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Men, this is no drill...

Nope, Towerdog, never heard of such a thing. However, you might give the Flight Safety Boeing school at DFW a call. They used to be Braniff airlines training center. They have probably trained more foreign airline crews than anybody else in the US. If there was such a mod they would know about it.

Con-pilot:

Uh, okay. Is that the old Dalforth Aviation?
Braniffs Training Center went intependent after poor old Braniff went Tango Uniform?

I trained there twice, 1988 and 1992, contract training on the whale.
First for Evergreen International, next time for my own $11,000 B-747-200 type rating.
Good school, good people.

Ah, nah, not that big of a deal, just thought a casual question on PPRuNe would clarify some old memories about the B-727 after burner.
Been to class lately on the 727 for AA and nobody ever heard of such an animal over there in Texas.
Therefore the posting.

It however would make sense to have extra power in the sand box, (Kuwait) as an engine failure at +54 C, even at sea level would slow down yer changes of climbing out of it.

Many times we took off with the B-747 and quit climbing at around 1000'.
We would neither climb, not accelerate.
Just hang there for several long minutes.
Inversion or something.
Would hate to think about loosing one under them conditions.
They have gotten away with it for years.
I guess Boeing builds good airplanes: Lots of margins.



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Men, this is no drill...

Uh, really bad torching???

Kinda neat if they did have burners though. That'd be a 72 I'd love to fly...

TowerDog, yes it is the old Dalfort school. I did recurrency there for ten years, also got my type rating there.

The most underpowered 72 I ever flew was an ex-Air France 200 that had -7 engines. I'm not kidding, -7s. With any load at all on board we were thrilled to make up to 290. What a dog. If any 72 needed a AB it was that one. I also got to fly a 100 with the P/W 217 (or 219s I can't remember now) on # 1 and #3 positions and a -9 in #2. Now that airplane was a rocket.

[This message has been edited by con-pilot (edited 21 December 2000).]

TowerDog
My curiosity was aroused by your comments re "sandbox" ops and "hanging" at 1000ft.
Do you recall what the met and loading conditions were.

I am a bit interested in the mechnism of the "inversion" to which you referred??

We get similar temps in outback Oz often outside the "chart" limits accompanied by what we call "willy willies" (localised heating mini tornado) which provide some interesting flying.

The -17R's would give you another 1000-1500 lbs of thrust in the event you lost an engine.

Gaunty:

Yes, conditions would be hot, usually +54C or more and sea level.
We would use flaps 20 for T/O as it was company police. The 747 climbs better with F-10 for T/O. Yet to save tires we used the higher flap setting and when it was time for clean up at 1000' or so, we would spend as much as 5 minuttes just sitting there, unable to accelerate or climb.
(Well, we would somehow get out of it by being patient or lucky, but it was a strange situation, yet it happened every time on really hot days and we were maxed out)

It would not have been a problem if we had used the lower flap setting. I did normal F-10 T/Os in Saudi for a different company and under similar met conditions, never had
a problem.

Inversion at 1000 feet? It could have been a layer of hotter air that robbed us of performance, but can not swear to it.
It was 7 years ago and my memory is somewhat teflon coated. :)

Iceman49: Ah, roger on the 17R engines giving higer boost: From some after burner arrangment or just more fuel into the fuel control unit?


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Men, this is no drill...

[This message has been edited by TowerDog (edited 23 December 2000).]

TowerDog
Ahhhhh now I understand about the F20/clean transition, sounds like the classic back of the power curve L/D ratio thingy to me, coupled with the reduced thrust/mass flow from engines panting a bit in the temps. Hanging whilst slowly crawling up the back with it gettting relatively (asymptotically) progressively better with increase in speed sound familiar? Still it would have given you a bit more time to get the after takeoff on the way.
Sometimes management just don't get it, in aerodynamics you ALWAYS pay one way or another. I would guess that whatever $s they thought they saved in tyres got pumped through the engines whilst you were sitting there hanging out. Would have been interesting had it hit the fan.
But then if you own half the worlds oil I dont spose it matters. :)

Gaunty:

Yes, you are right on, the savings were blown out the tail pipe.
But, besides that, I was always wondering what would happpen if we has lost an engine just after V1.
Probably be bouncing across the desert in ground effect while dumping fuel and praying to Allah for forgivenes. :)

Another factor is that the temp could have been higher than officialy reported: If the control tower had issued actual temps instead of staying one degree under the Boeing/Airbus maximum limitations, then uh, they would have to shut the airport down as no flights could legaly take off and land.
For some reason the "official" temp never exceeded that limit. (Was it +54 C for the Boeing)
Hmm, would they do that on purpose?
Nah, those nice men in nightgowns over there would never do that each other. :) :) :)

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Men, this is no drill...

[This message has been edited by TowerDog (edited 24 December 2000).]

TowerDog
Ahhhhh now I understand about the F20/clean transition, sounds like the classic back of the power curve L/D ratio thingy to me, coupled with the reduced thrust/mass flow from engines panting a bit in the temps. Hanging whilst slowly crawling up the back with it gettting relatively (asymptotically) progressively better with increase in speed sound familiar? Still it would have given you a bit more time to get the after takeoff coffee on the way.
Sometimes management just don't get it, in aerodynamics you ALWAYS pay one way or another. I would guess that whatever $s they thought they saved in tyres got pumped through the engines whilst you were sitting there hanging out. Would have been interesting had it hit the fan.
But then if you own half the worlds oil I dont spose it matters. :)


[This message has been edited by gaunty (edited 24 December 2000).]

TowerDog and Gaunty,

What you were experiencing were temperature inversions, they are extremely common in this part of the world. We started monitoring them about 4 years ago and have recorded inversions of up to 16°C, for obvious reasons they are extremely prevalent at night and during the summer. The Saudi Met Office forecasts these inversions and will probably supply the information to any crew that ask.

During these inversions we actually base our takeoff weights on the inversion temperature (Forecast or PIREPS) and not the actual airport temperature. This costs us a fortune in extra technical landings, but as crewmembers talk about the aircraft hanging in the air with all engines working, we really don’t want to find out what happens if one fails.

Mutt :)


[This message has been edited by mutt (edited 25 December 2000).]

Mutt:

Thanks for above refresher.
Yes, I flew in Saudi most of 1998 and seem to remember some inversion forecast.
Good info for sure. Especially if dispatched for a long and heavy flight.

The incidents mentioned in the topic above was before they issued any "Inversion Forecast". :)

Sure could have used 'em.
Or a flap 10 policy...

On a different note, since we are in the Tech forum: I flew small planes in Alaska years ago.
On cold winter mornings the density altitude was 5000 feet below sea level.
For piston planes certified only at full power (No reduced) we were not legal to take off as a 300 HP engine would develop 320 HP or so. And it was not certified for that kind of action.

Asked an FAA inspector about it one fine day as we were bored and grounded due to snow storms and such.
He shrugged it off and wanted no part of the problem.

Perhaps same with the high temps, inversions in the sand-box?
Who actually gives a turd if all the mills keep spinning?

Not the pilots?
Not the company?
Not the state?
Not the union?
Not the pax?

If the pax did know, would they cancel the reservation after they got the ATIS, or would they just get on, strap in and wish to wake up in LHR 6 later?




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Men, this is no drill...

All this talk about 727´s with afterburners... I wish.
I am still flying a -100 with Dash 7 engines. With our weights Riyadh during summer is a real drag. We use every bit of the available runway.

JJ

TowerDog,

Were you guys doing the Malaysian Hadj or the Nigerian Hadj in 98? We really miss the Tower parties in Durat.

As for your 320hp piston, you would have had a great time flying it, nobody would have cared until you bent it!

JJFlyer.
RUH has almost 14,000 ft of runway, just how much do you guys need?? :)

Mutt:

We did a Saudia Hadj in 98 and stayed at the Durat at the beach. (Also did a bunch of regular civilian SA flights the rest of the year. Got pretty tired of the place.

Did an Air India Hadj in 99.

Too many Hadjes, think I have done 6.

Yeah, that C-185 at 5000' below sea-level performed quite well. :)



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Men, this is no drill...