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phugoid1982
Topic Author
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Concorde time spent at max thrust with full reheat

Thu Jun 23, 2022 2:47 pm

I know most commercial aircraft can only maintain max thrust for a a few mins and then will switch to max climb thrust and have a Max continuous thrust limit to limit engine wear and tear. Concorde accelerated from Mach .98 to Mach 1.7 from 28000ft to 45-47000ft full thrust and reheat was applied until it cruise climbed to TOD~60000ft. Assuming a rate of climb between 1000 ft to 2000 I'll assume this took between 10 to 15 minutes to the cruise climb point. Far greater spent at max thrust than most aircraft and done routinely. What was the max time Concorde could spend at this power setting for routine use with and without reheat? Also, any specific metallurgical details as to how this was achieved would be appreciated. Thanks.
 
kalvado
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Joined: Wed Mar 01, 2006 4:29 am

Re: Concorde time spent at max thrust with full reheat

Thu Jun 23, 2022 3:52 pm

Reheat is used on every take-off, its light-up sequence taking place on the roll as the engines accelerates up to full power – it needs the mass flow associated with an N1 of 81% or more to function. It is switched off at 500ft on a standard flight or at noise abatement cut-back where needed. For the transonic acceleration it is switched on at climb power at M0.95, then off again at M1.7 – a run of between 10 and 15 minutes dependent upon aircraft weight and outside air temperature

https://www.heritageconcorde.com/concor ... e-re-heats
Since reheat runs at the very end of engine flow, I assume not many - if any - parts were exposed to temperature. Nozzle may be protected by colder flow areas.
 
kalvado
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Re: Concorde time spent at max thrust with full reheat

Thu Jun 23, 2022 4:17 pm

And for metallurgy:
Image
 
tu144d
Posts: 217
Joined: Wed Apr 24, 2002 11:39 pm

Re: Concorde time spent at max thrust with full reheat

Thu Jun 23, 2022 4:37 pm

kalvado wrote:
Reheat is used on every take-off, its light-up sequence taking place on the roll as the engines accelerates up to full power – it needs the mass flow associated with an N1 of 81% or more to function. It is switched off at 500ft on a standard flight or at noise abatement cut-back where needed. For the transonic acceleration it is switched on at climb power at M0.95, then off again at M1.7 – a run of between 10 and 15 minutes dependent upon aircraft weight and outside air temperature

https://www.heritageconcorde.com/concor ... e-re-heats
Since reheat runs at the very end of engine flow, I assume not many - if any - parts were exposed to temperature. Nozzle may be protected by colder flow areas.


Interesting stuff. It always impressed me how Concorde engineers effectively used fuel as a heat sink to cool the fuselage and yet the Russians with the TU-144 couldn't get if figured out and used gigantic air conditioners that made so much nose normal conversation was impossible aboard it.
 
Yikes!
Posts: 406
Joined: Sat Oct 13, 2001 4:51 pm

Re: Concorde time spent at max thrust with full reheat

Thu Jun 23, 2022 10:10 pm

tu144d wrote:
kalvado wrote:
Reheat is used on every take-off, its light-up sequence taking place on the roll as the engines accelerates up to full power – it needs the mass flow associated with an N1 of 81% or more to function. It is switched off at 500ft on a standard flight or at noise abatement cut-back where needed. For the transonic acceleration it is switched on at climb power at M0.95, then off again at M1.7 – a run of between 10 and 15 minutes dependent upon aircraft weight and outside air temperature

https://www.heritageconcorde.com/concor ... e-re-heats
Since reheat runs at the very end of engine flow, I assume not many - if any - parts were exposed to temperature. Nozzle may be protected by colder flow areas.


Interesting stuff. It always impressed me how Concorde engineers effectively used fuel as a heat sink to cool the fuselage and yet the Russians with the TU-144 couldn't get if figured out and used gigantic air conditioners that made so much nose normal conversation was impossible aboard it.


Last thing first: normal noise on BA/AF Concorde during flight was so loud as to prohibit normal conversation - one had to raise their voice to be heard. I used ear plugs on my flight.
Re-heat (afterburner) was used only during takeoff, cancelled after entry into third segment climb, and then again, from the acceleration from M.090 to ~M1.7 then shutdown once a stable Mach climb was established. Acceleration to M2.0 and climb to apogee was strictly on engine thrust, no re-heat (afterburner).

Hoping that adds to your understanding.
 
GalaxyFlyer
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Re: Concorde time spent at max thrust with full reheat

Thu Jun 23, 2022 10:27 pm

Burners were only on KJFK for about 1 minute, canceled for noise, then basic engine up to the transonic checklist with AB selected abound .93 and maintained until M1.7. Climb rate was higher than 1000-2000fpm, likely around 3000fpm while climbing to M1.7. All this from Bellerophon’s post years ago in PPRUNE.
 
Max Q
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Re: Concorde time spent at max thrust with full reheat

Fri Jun 24, 2022 2:17 am

I believe the maximum time in reheat was 15 minutes
 
phugoid1982
Topic Author
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Re: Concorde time spent at max thrust with full reheat

Fri Jun 24, 2022 10:32 am

Yikes! wrote:
tu144d wrote:
kalvado wrote:
https://www.heritageconcorde.com/concor ... e-re-heats
Since reheat runs at the very end of engine flow, I assume not many - if any - parts were exposed to temperature. Nozzle may be protected by colder flow areas.


Interesting stuff. It always impressed me how Concorde engineers effectively used fuel as a heat sink to cool the fuselage and yet the Russians with the TU-144 couldn't get if figured out and used gigantic air conditioners that made so much nose normal conversation was impossible aboard it.


Last thing first: normal noise on BA/AF Concorde during flight was so loud as to prohibit normal conversation - one had to raise their voice to be heard. I used ear plugs on my flight.
Re-heat (afterburner) was used only during takeoff, cancelled after entry into third segment climb, and then again, from the acceleration from M.090 to ~M1.7 then shutdown once a stable Mach climb was established. Acceleration to M2.0 and climb to apogee was strictly on engine thrust, no re-heat (afterburner).

Hoping that adds to your understanding.


Interesting about the noise. That was a typo on my part. I knew the afterburners were shut down at Mach 1.7. I can't imagine (engine wear and tear aside) what the range on Concorde would be reheats engaged continuously. Probably 1500 nm
 
kalvado
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Re: Concorde time spent at max thrust with full reheat

Fri Jun 24, 2022 11:33 am

Max Q wrote:
I believe the maximum time in reheat was 15 minutes

Is that limited by fuel tank capacity?
 
Legs
Posts: 275
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Re: Concorde time spent at max thrust with full reheat

Fri Jun 24, 2022 12:57 pm

kalvado wrote:
Is that limited by fuel tank capacity?


Certainly in military circles, afterburner limitations are mostly driven by heat management; nozzles, exhaust ducts, surrounding structure etc. I suspect that Concorde would be no different.
 
kalvado
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Re: Concorde time spent at max thrust with full reheat

Fri Jun 24, 2022 1:31 pm

Legs wrote:
kalvado wrote:
Is that limited by fuel tank capacity?


Certainly in military circles, afterburner limitations are mostly driven by heat management; nozzles, exhaust ducts, surrounding structure etc. I suspect that Concorde would be no different.

Certainly supply of humor to military was recently cut by Congress during funding negotiations.
 
GDB
Posts: 15646
Joined: Wed May 23, 2001 6:25 pm

Re: Concorde time spent at max thrust with full reheat

Fri Jun 24, 2022 2:23 pm

Yikes! wrote:
tu144d wrote:
kalvado wrote:
https://www.heritageconcorde.com/concor ... e-re-heats
Since reheat runs at the very end of engine flow, I assume not many - if any - parts were exposed to temperature. Nozzle may be protected by colder flow areas.


Interesting stuff. It always impressed me how Concorde engineers effectively used fuel as a heat sink to cool the fuselage and yet the Russians with the TU-144 couldn't get if figured out and used gigantic air conditioners that made so much nose normal conversation was impossible aboard it.


Last thing first: normal noise on BA/AF Concorde during flight was so loud as to prohibit normal conversation - one had to raise their voice to be heard. I used ear plugs on my flight.
Re-heat (afterburner) was used only during takeoff, cancelled after entry into third segment climb, and then again, from the acceleration from M.090 to ~M1.7 then shutdown once a stable Mach climb was established. Acceleration to M2.0 and climb to apogee was strictly on engine thrust, no re-heat (afterburner).

Hoping that adds to your understanding.


I never had any trouble, not having to raise my voice on my 7 flights, 5 of which were standard pax, one was a full pax LHR-JFK simulation (LHR-LHR but same speed, altitude, duration), one was a pretty full retirement flight for G-BOAE to BGI, if you are going by You Tube videos note the cameras (pre smartphone too), accentuated cabin noise. As on conventional airliners.
Maybe a decent quality one of a professional film crew.

The TU-144 apparently was so loud pax had to pass written messages, however very few 'pax' flights flown, foreign journalists picked that up.

Had the noise been as loud as you claim, at least for most people, I accept some for various reasons might find it louder, then again some are more sensitive to aircraft motions too, well, BA would have struggled to keep all those regular pax for all those years.
Saying that, do you have, not intruding here I hope, sensitive hearing?
It was louder (as are all aircraft) on take off, down the back it was known as 'rocket class', again that just illustrates what one of the type's Chief Pilots said, 'it's just another aircraft only more so'.
 
tu144d
Posts: 217
Joined: Wed Apr 24, 2002 11:39 pm

Re: Concorde time spent at max thrust with full reheat

Fri Jun 24, 2022 6:06 pm

GDB wrote:
Yikes! wrote:
tu144d wrote:

Interesting stuff. It always impressed me how Concorde engineers effectively used fuel as a heat sink to cool the fuselage and yet the Russians with the TU-144 couldn't get if figured out and used gigantic air conditioners that made so much nose normal conversation was impossible aboard it.


Last thing first: normal noise on BA/AF Concorde during flight was so loud as to prohibit normal conversation - one had to raise their voice to be heard. I used ear plugs on my flight.
Re-heat (afterburner) was used only during takeoff, cancelled after entry into third segment climb, and then again, from the acceleration from M.090 to ~M1.7 then shutdown once a stable Mach climb was established. Acceleration to M2.0 and climb to apogee was strictly on engine thrust, no re-heat (afterburner).

Hoping that adds to your understanding.


I never had any trouble, not having to raise my voice on my 7 flights, 5 of which were standard pax, one was a full pax LHR-JFK simulation (LHR-LHR but same speed, altitude, duration), one was a pretty full retirement flight for G-BOAE to BGI, if you are going by You Tube videos note the cameras (pre smartphone too), accentuated cabin noise. As on conventional airliners.
Maybe a decent quality one of a professional film crew.

The TU-144 apparently was so loud pax had to pass written messages, however very few 'pax' flights flown, foreign journalists picked that up.

Had the noise been as loud as you claim, at least for most people, I accept some for various reasons might find it louder, then again some are more sensitive to aircraft motions too, well, BA would have struggled to keep all those regular pax for all those years.
Saying that, do you have, not intruding here I hope, sensitive hearing?
It was louder (as are all aircraft) on take off, down the back it was known as 'rocket class', again that just illustrates what one of the type's Chief Pilots said, 'it's just another aircraft only more so'.


Apparently the latter version of Tu-144D (D model) used a non-afterburning translating plug variable nozzle engine (Kolesov RD-36-51A). I posted a thread about this trying to more info but got no replies. It never flew pax and and there was a fuel line issue which caused a crash that promptly resulting in Aeroflot terminating the commercial flights even though those aircraft used different afterburning NK-144 turbojets. Either way they flew transcontinental test flights from Moscow to Khabarovsk in the fear east successfully a few times. I think that would make the TU-144D the first SST or any supersonic aircraft for that matter, to use a non-afterburning turbojet the first aircraft to supercruise. Can't verify this though. Shame, if it weren't for the oil-crisis and Aeroflot's lack of enthusiasm the Soviets might have been able to work out the kinks with a few more years.
 
Tristarsteve
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Re: Concorde time spent at max thrust with full reheat

Fri Jun 24, 2022 6:40 pm

I would like to second GDB post on the internal noise. Only flew once on Concorde, and AF one from ARN. Thge noise inside was quite acceptable and no higher than other narrow bodies of the time.
Noise outside was something else! Our staff car park at LHR was at the end of 28L. When Concorde left in the morning, the noise and airflow set off all the car alarms in the car park.
 
kalvado
Posts: 3747
Joined: Wed Mar 01, 2006 4:29 am

Re: Concorde time spent at max thrust with full reheat

Fri Jun 24, 2022 6:51 pm

tu144d wrote:
GDB wrote:
Yikes! wrote:

Last thing first: normal noise on BA/AF Concorde during flight was so loud as to prohibit normal conversation - one had to raise their voice to be heard. I used ear plugs on my flight.
Re-heat (afterburner) was used only during takeoff, cancelled after entry into third segment climb, and then again, from the acceleration from M.090 to ~M1.7 then shutdown once a stable Mach climb was established. Acceleration to M2.0 and climb to apogee was strictly on engine thrust, no re-heat (afterburner).

Hoping that adds to your understanding.


I never had any trouble, not having to raise my voice on my 7 flights, 5 of which were standard pax, one was a full pax LHR-JFK simulation (LHR-LHR but same speed, altitude, duration), one was a pretty full retirement flight for G-BOAE to BGI, if you are going by You Tube videos note the cameras (pre smartphone too), accentuated cabin noise. As on conventional airliners.
Maybe a decent quality one of a professional film crew.

The TU-144 apparently was so loud pax had to pass written messages, however very few 'pax' flights flown, foreign journalists picked that up.

Had the noise been as loud as you claim, at least for most people, I accept some for various reasons might find it louder, then again some are more sensitive to aircraft motions too, well, BA would have struggled to keep all those regular pax for all those years.
Saying that, do you have, not intruding here I hope, sensitive hearing?
It was louder (as are all aircraft) on take off, down the back it was known as 'rocket class', again that just illustrates what one of the type's Chief Pilots said, 'it's just another aircraft only more so'.


Apparently the latter version of Tu-144D (D model) used a non-afterburning translating plug variable nozzle engine (Kolesov RD-36-51A). I posted a thread about this trying to more info but got no replies. It never flew pax and and there was a fuel line issue which caused a crash that promptly resulting in Aeroflot terminating the commercial flights even though those aircraft used different afterburning NK-144 turbojets. Either way they flew transcontinental test flights from Moscow to Khabarovsk in the fear east successfully a few times. I think that would make the TU-144D the first SST or any supersonic aircraft for that matter, to use a non-afterburning turbojet the first aircraft to supercruise. Can't verify this though. Shame, if it weren't for the oil-crisis and Aeroflot's lack of enthusiasm the Soviets might have been able to work out the kinks with a few more years.

I suspect going through M=1.0 would still require an afterburner. I don't think any plane today can accelerate supersonic on turbojet/turbofan with no afterburn.
Supersonic cruise without an afterburner is the general goal.
On a separate note - is it delta wing that requires a lot of takeoff thrust that an afterburner was required on a runway for both SSTs?
 
Max Q
Posts: 9244
Joined: Wed May 09, 2001 12:40 pm

Re: Concorde time spent at max thrust with full reheat

Fri Jun 24, 2022 7:20 pm

kalvado wrote:
Max Q wrote:
I believe the maximum time in reheat was 15 minutes

Is that limited by fuel tank capacity?



Probably and perhaps an engine limitation, IIRC that was enough time to allow the acceleration from .95 at mid altitudes to 1.7 Mach around FL 450 after a steady accelerating cruise climb continuing at lower rate in dry power reaching M2 at FL500 then cruise climbing as fuel was burned off up to a maximum of FL600


I remember this 15 minute restriction from John Hutchinson’s excellent podcast on flying Concorde


He is a retired BA Captain who flew that aircraft for 15 years during a long career at that airline

It’s fascinating and educational, worth looking up
 
kalvado
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Re: Concorde time spent at max thrust with full reheat

Fri Jun 24, 2022 7:38 pm

Max Q wrote:
kalvado wrote:
Max Q wrote:
I believe the maximum time in reheat was 15 minutes

Is that limited by fuel tank capacity?



Probably and perhaps an engine limitation, IIRC that was enough time to allow the acceleration from .95 at mid altitudes to 1.7 Mach around FL 450 after a steady accelerating cruise climb continuing at lower rate in dry power reaching M2 at FL500 then cruise climbing as fuel was burned off up to a maximum of FL600


I remember this 15 minute restriction from John Hutchinson’s excellent podcast on flying Concorde


He is a retired BA Captain who flew that aircraft for 15 years during a long career at that airline

It’s fascinating and educational, worth looking up

Of course it is an engine limitation, but to explain where I am coming from:
afterburner is a hugely inefficient and fuel hungry thing.
For Concorde, going full afterburner increased fuel consumption more than 2x compared to full thrust. 32.5 liters a second total, or 22500 kg/hour per engine are quoted.
With fuel capacity of 119,500 litres or 95,680 kgs that corresponds to 1 hour 01 minute or 1 hour 03 minutes run from full tanks to zero - these numbers match within the accuracy of calculation.
So, with deceleration, taxi and landing fuel, and required reserves, I doubt Concorde would have more than 30-40 min of afterburner time in fuel even without engine limitations

I hope this explains the joke. Please feel free to ask for further explanation if I still missed it.
 
tu144d
Posts: 217
Joined: Wed Apr 24, 2002 11:39 pm

Re: Concorde time spent at max thrust with full reheat

Fri Jun 24, 2022 8:47 pm

kalvado wrote:
tu144d wrote:
GDB wrote:

I never had any trouble, not having to raise my voice on my 7 flights, 5 of which were standard pax, one was a full pax LHR-JFK simulation (LHR-LHR but same speed, altitude, duration), one was a pretty full retirement flight for G-BOAE to BGI, if you are going by You Tube videos note the cameras (pre smartphone too), accentuated cabin noise. As on conventional airliners.
Maybe a decent quality one of a professional film crew.

The TU-144 apparently was so loud pax had to pass written messages, however very few 'pax' flights flown, foreign journalists picked that up.

Had the noise been as loud as you claim, at least for most people, I accept some for various reasons might find it louder, then again some are more sensitive to aircraft motions too, well, BA would have struggled to keep all those regular pax for all those years.
Saying that, do you have, not intruding here I hope, sensitive hearing?
It was louder (as are all aircraft) on take off, down the back it was known as 'rocket class', again that just illustrates what one of the type's Chief Pilots said, 'it's just another aircraft only more so'.


Apparently the latter version of Tu-144D (D model) used a non-afterburning translating plug variable nozzle engine (Kolesov RD-36-51A). I posted a thread about this trying to more info but got no replies. It never flew pax and and there was a fuel line issue which caused a crash that promptly resulting in Aeroflot terminating the commercial flights even though those aircraft used different afterburning NK-144 turbojets. Either way they flew transcontinental test flights from Moscow to Khabarovsk in the fear east successfully a few times. I think that would make the TU-144D the first SST or any supersonic aircraft for that matter, to use a non-afterburning turbojet the first aircraft to supercruise. Can't verify this though. Shame, if it weren't for the oil-crisis and Aeroflot's lack of enthusiasm the Soviets might have been able to work out the kinks with a few more years.

I suspect going through M=1.0 would still require an afterburner. I don't think any plane today can accelerate supersonic on turbojet/turbofan with no afterburn.
Supersonic cruise without an afterburner is the general goal.
On a separate note - is it delta wing that requires a lot of takeoff thrust that an afterburner was required on a runway for both SSTs?


The book by Gordon/yefim and Wikipedia state the rd-36 was non afterburning. Getting through Drag divergence is the big hurdle. Once past that thrust isn't the limitation on Max Mach. It's materials. The issue with the delta wing is that its slope of Lift coefficient vs angle of attack is much more shallow than that of a conventional wing hence the higher takeoff speed which results in very high tire rotation speeds which may have been the culprit in Concorde having various tire burst incidents.
 
Yikes!
Posts: 406
Joined: Sat Oct 13, 2001 4:51 pm

Re: Concorde time spent at max thrust with full reheat

Fri Jun 24, 2022 8:52 pm

GDB wrote:
Yikes! wrote:
tu144d wrote:

Interesting stuff. It always impressed me how Concorde engineers effectively used fuel as a heat sink to cool the fuselage and yet the Russians with the TU-144 couldn't get if figured out and used gigantic air conditioners that made so much nose normal conversation was impossible aboard it.


Last thing first: normal noise on BA/AF Concorde during flight was so loud as to prohibit normal conversation - one had to raise their voice to be heard. I used ear plugs on my flight.
Re-heat (afterburner) was used only during takeoff, cancelled after entry into third segment climb, and then again, from the acceleration from M.090 to ~M1.7 then shutdown once a stable Mach climb was established. Acceleration to M2.0 and climb to apogee was strictly on engine thrust, no re-heat (afterburner).

Hoping that adds to your understanding.


I never had any trouble, not having to raise my voice on my 7 flights, 5 of which were standard pax, one was a full pax LHR-JFK simulation (LHR-LHR but same speed, altitude, duration), one was a pretty full retirement flight for G-BOAE to BGI, if you are going by You Tube videos note the cameras (pre smartphone too), accentuated cabin noise. As on conventional airliners.
Maybe a decent quality one of a professional film crew.

The TU-144 apparently was so loud pax had to pass written messages, however very few 'pax' flights flown, foreign journalists picked that up.

Had the noise been as loud as you claim, at least for most people, I accept some for various reasons might find it louder, then again some are more sensitive to aircraft motions too, well, BA would have struggled to keep all those regular pax for all those years.
Saying that, do you have, not intruding here I hope, sensitive hearing?
It was louder (as are all aircraft) on take off, down the back it was known as 'rocket class', again that just illustrates what one of the type's Chief Pilots said, 'it's just another aircraft only more so'.

Thanks for that. My recollection is from the notes I took in 1996 LHR-JFK. I was in 9A. I do recall hearing the fuel transfer pumps so perhaps my inflight hearing wasn't as bad as I recollect! I did get a visit to the flight deck as it seemed it was every passenger's rights back in the day. But the Skipper told me I was the only one that ASKED to visit the flight deck in flight - I was up there for nearly 10 minutes! Glad to hear you had multiple trips - I'm jealous. Just sayin'...!
 
mxaxai
Posts: 3295
Joined: Sat Jun 18, 2016 7:29 am

Re: Concorde time spent at max thrust with full reheat

Fri Jun 24, 2022 10:27 pm

kalvado wrote:
I suspect going through M=1.0 would still require an afterburner. I don't think any plane today can accelerate supersonic on turbojet/turbofan with no afterburn.
Supersonic cruise without an afterburner is the general goal.

Most modern fighter jets can accelerate to supersonic speeds without afterburner in a clean configuration. Some may need to dive and exchange altitude for speed during the transition. In general, you'd want to spend as little time as possible at transonic speeds for efficiency reasons, so either a shallow dive and/or afterburners are used to get to the more efficient supersonic (supercruise) regime.
 
kalvado
Posts: 3747
Joined: Wed Mar 01, 2006 4:29 am

Re: Concorde time spent at max thrust with full reheat

Fri Jun 24, 2022 10:45 pm

mxaxai wrote:
kalvado wrote:
I suspect going through M=1.0 would still require an afterburner. I don't think any plane today can accelerate supersonic on turbojet/turbofan with no afterburn.
Supersonic cruise without an afterburner is the general goal.

Most modern fighter jets can accelerate to supersonic speeds without afterburner in a clean configuration. Some may need to dive and exchange altitude for speed during the transition. In general, you'd want to spend as little time as possible at transonic speeds for efficiency reasons, so either a shallow dive and/or afterburners are used to get to the more efficient supersonic (supercruise) regime.

I wonder if a shallow dive would be acceptable for a passenger SST...
 
phugoid1982
Topic Author
Posts: 331
Joined: Sat Sep 10, 2016 4:02 am

Re: Concorde time spent at max thrust with full reheat

Fri Jun 24, 2022 10:50 pm

mxaxai wrote:
kalvado wrote:
I suspect going through M=1.0 would still require an afterburner. I don't think any plane today can accelerate supersonic on turbojet/turbofan with no afterburn.
Supersonic cruise without an afterburner is the general goal.

Most modern fighter jets can accelerate to supersonic speeds without afterburner in a clean configuration. Some may need to dive and exchange altitude for speed during the transition. In general, you'd want to spend as little time as possible at transonic speeds for efficiency reasons, so either a shallow dive and/or afterburners are used to get to the more efficient supersonic (supercruise) regime.


I remember vaguely in my Optimal Control class in Aeronautical Engineering the prof proved the optimal path for most supersonic aircraft to attain Mach 2.0 was to climb to somewhere around 35kft and dive to accelerate past drag divergence Mach number exchanging potential for kinetic energy then climbing again. Of course the major limitation here being the stress due to dynamic pressure at such low altitudes.
 
GalaxyFlyer
Posts: 9633
Joined: Fri Jan 01, 2016 4:44 am

Re: Concorde time spent at max thrust with full reheat

Sat Jun 25, 2022 1:20 am

That’s how the SR did it—the dipsy-doodle off the tanker.
 
GDB
Posts: 15646
Joined: Wed May 23, 2001 6:25 pm

Re: Concorde time spent at max thrust with full reheat

Sat Jun 25, 2022 6:58 am

Yikes! wrote:
GDB wrote:
Yikes! wrote:

Last thing first: normal noise on BA/AF Concorde during flight was so loud as to prohibit normal conversation - one had to raise their voice to be heard. I used ear plugs on my flight.
Re-heat (afterburner) was used only during takeoff, cancelled after entry into third segment climb, and then again, from the acceleration from M.090 to ~M1.7 then shutdown once a stable Mach climb was established. Acceleration to M2.0 and climb to apogee was strictly on engine thrust, no re-heat (afterburner).

Hoping that adds to your understanding.


I never had any trouble, not having to raise my voice on my 7 flights, 5 of which were standard pax, one was a full pax LHR-JFK simulation (LHR-LHR but same speed, altitude, duration), one was a pretty full retirement flight for G-BOAE to BGI, if you are going by You Tube videos note the cameras (pre smartphone too), accentuated cabin noise. As on conventional airliners.
Maybe a decent quality one of a professional film crew.

The TU-144 apparently was so loud pax had to pass written messages, however very few 'pax' flights flown, foreign journalists picked that up.

Had the noise been as loud as you claim, at least for most people, I accept some for various reasons might find it louder, then again some are more sensitive to aircraft motions too, well, BA would have struggled to keep all those regular pax for all those years.
Saying that, do you have, not intruding here I hope, sensitive hearing?
It was louder (as are all aircraft) on take off, down the back it was known as 'rocket class', again that just illustrates what one of the type's Chief Pilots said, 'it's just another aircraft only more so'.

Thanks for that. My recollection is from the notes I took in 1996 LHR-JFK. I was in 9A. I do recall hearing the fuel transfer pumps so perhaps my inflight hearing wasn't as bad as I recollect! I did get a visit to the flight deck as it seemed it was every passenger's rights back in the day. But the Skipper told me I was the only one that ASKED to visit the flight deck in flight - I was up there for nearly 10 minutes! Glad to hear you had multiple trips - I'm jealous. Just sayin'...!


It was a great part of many peoples experience that cockpit visit, especially during all those charters, though crew told me that getting most of the 100 pax a look on what was usually a shorter flight was a challenge.
After those deluded, mad, human hating specimens did Sept 11, that ended of course, I mentioned above a simulated full pax flight LHR-LHR, it was part of the return to service after the AF accident, as planned the flight turned at 30W and we landed back at LHR, as it turned out into a different world from what we took off from just 3.5 hours. Since the date was September 11th 2001.
I had been at BA 14 years when I joined BA Concorde Engineering in 1997, in November 1993, I got my first Concorde flight via staff concessions, IAD-LHR.
As were the other pax flights, save the last, longest, highest (60,000ft) on the longer leg to BGI.

Feeling the reheats come on at Mach 0.95, I cannot say I felt them come in despite knowing, due to the cabin bulkhead displays, when they were, with two exceptions, despite being in the forward cabin on that fateful 2001 flight, though being engaged two at a time also lessened feeling, as well as my last, that last one for G-BOAE to BGI in November 1993, then I was in the rearmost row.
I sad four pax flights, one actually had very few pax and was also LHR-LHR, since it was a post engineering test flight.
So I was lucky, in a right place/right time way.
 
phugoid1982
Topic Author
Posts: 331
Joined: Sat Sep 10, 2016 4:02 am

Re: Concorde time spent at max thrust with full reheat

Sat Jun 25, 2022 10:13 am

GDB wrote:
Yikes! wrote:
GDB wrote:

I never had any trouble, not having to raise my voice on my 7 flights, 5 of which were standard pax, one was a full pax LHR-JFK simulation (LHR-LHR but same speed, altitude, duration), one was a pretty full retirement flight for G-BOAE to BGI, if you are going by You Tube videos note the cameras (pre smartphone too), accentuated cabin noise. As on conventional airliners.
Maybe a decent quality one of a professional film crew.

The TU-144 apparently was so loud pax had to pass written messages, however very few 'pax' flights flown, foreign journalists picked that up.

Had the noise been as loud as you claim, at least for most people, I accept some for various reasons might find it louder, then again some are more sensitive to aircraft motions too, well, BA would have struggled to keep all those regular pax for all those years.
Saying that, do you have, not intruding here I hope, sensitive hearing?
It was louder (as are all aircraft) on take off, down the back it was known as 'rocket class', again that just illustrates what one of the type's Chief Pilots said, 'it's just another aircraft only more so'.

Thanks for that. My recollection is from the notes I took in 1996 LHR-JFK. I was in 9A. I do recall hearing the fuel transfer pumps so perhaps my inflight hearing wasn't as bad as I recollect! I did get a visit to the flight deck as it seemed it was every passenger's rights back in the day. But the Skipper told me I was the only one that ASKED to visit the flight deck in flight - I was up there for nearly 10 minutes! Glad to hear you had multiple trips - I'm jealous. Just sayin'...!


It was a great part of many peoples experience that cockpit visit, especially during all those charters, though crew told me that getting most of the 100 pax a look on what was usually a shorter flight was a challenge.
After those deluded, mad, human hating specimens did Sept 11, that ended of course, I mentioned above a simulated full pax flight LHR-LHR, it was part of the return to service after the AF accident, as planned the flight turned at 30W and we landed back at LHR, as it turned out into a different world from what we took off from just 3.5 hours. Since the date was September 11th 2001.
I had been at BA 14 years when I joined BA Concorde Engineering in 1997, in November 1993, I got my first Concorde flight via staff concessions, IAD-LHR.
As were the other pax flights, save the last, longest, highest (60,000ft) on the longer leg to BGI.

Feeling the reheats come on at Mach 0.95, I cannot say I felt them come in despite knowing, due to the cabin bulkhead displays, when they were, with two exceptions, despite being in the forward cabin on that fateful 2001 flight, though being engaged two at a time also lessened feeling, as well as my last, that last one for G-BOAE to BGI in November 1993, then I was in the rearmost row.
I sad four pax flights, one actually had very few pax and was also LHR-LHR, since it was a post engineering test flight.
So I was lucky, in a right place/right time way.


Apart from getting to fly on Concorde, working for BA Concorde Engineering must've been an incredible experience with quite a few stories to tell!!!
 
phugoid1982
Topic Author
Posts: 331
Joined: Sat Sep 10, 2016 4:02 am

Re: Concorde time spent at max thrust with full reheat

Sat Jun 25, 2022 10:23 am

GalaxyFlyer wrote:
That’s how the SR did it—the dipsy-doodle off the tanker.


I was gonna post this in my previous comment but was racking my brain trying to figure out the name of the maneuver!
 
26point2
Posts: 1156
Joined: Wed Mar 03, 2010 6:01 am

Re: Concorde time spent at max thrust with full reheat

Sun Jun 26, 2022 1:06 pm

GDB wrote:
Yikes! wrote:
tu144d wrote:

Interesting stuff. It always impressed me how Concorde engineers effectively used fuel as a heat sink to cool the fuselage and yet the Russians with the TU-144 couldn't get if figured out and used gigantic air conditioners that made so much nose normal conversation was impossible aboard it.


Last thing first: normal noise on BA/AF Concorde during flight was so loud as to prohibit normal conversation - one had to raise their voice to be heard. I used ear plugs on my flight.
Re-heat (afterburner) was used only during takeoff, cancelled after entry into third segment climb, and then again, from the acceleration from M.090 to ~M1.7 then shutdown once a stable Mach climb was established. Acceleration to M2.0 and climb to apogee was strictly on engine thrust, no re-heat (afterburner).

Hoping that adds to your understanding.


I never had any trouble, not having to raise my voice on my 7 flights, 5 of which were standard pax, one was a full pax LHR-JFK simulation (LHR-LHR but same speed, altitude, duration), one was a pretty full retirement flight for G-BOAE to BGI, if you are going by You Tube videos note the cameras (pre smartphone too), accentuated cabin noise. As on conventional airliners.
Maybe a decent quality one of a professional film crew.

The TU-144 apparently was so loud pax had to pass written messages, however very few 'pax' flights flown, foreign journalists picked that up.

Had the noise been as loud as you claim, at least for most people, I accept some for various reasons might find it louder, then again some are more sensitive to aircraft motions too, well, BA would have struggled to keep all those regular pax for all those years.
Saying that, do you have, not intruding here I hope, sensitive hearing?
It was louder (as are all aircraft) on take off, down the back it was known as 'rocket class', again that just illustrates what one of the type's Chief Pilots said, 'it's just another aircraft only more so'.


I sat about 2/3rds of the way back at the window on BA 002 JFK-LHR. I recollect only two segments of that flight where high engine trust and cabin noise was noticeable…during the takeoff and first minute thereafter, and during landing. It seems the high angle of attack during final approach required Concorde to carry a lot of thrust down to retard. At least that’s my perception. Nonetheless it was unique and unlike a standard airliner landing.
 
accentra
Posts: 134
Joined: Wed Dec 15, 2021 11:35 pm

Re: Concorde time spent at max thrust with full reheat

Wed Jun 29, 2022 10:12 pm

From experience, have to concur. If you were sat away from the rear then the noise levels in Concorde were pretty much the same as any other contemporary jet aircraft. Think that was one of the design goals? And even then it was really only on TO. It was all about supersonic being no different than the norm. There's a famous quote re one of the test flights/demos about something like (and I'm paraphrasing): 'it's not extraordinary' and 'yes, that was the hard part!'.
 
GDB
Posts: 15646
Joined: Wed May 23, 2001 6:25 pm

Re: Concorde time spent at max thrust with full reheat

Thu Jun 30, 2022 10:59 am

accentra wrote:
From experience, have to concur. If you were sat away from the rear then the noise levels in Concorde were pretty much the same as any other contemporary jet aircraft. Think that was one of the design goals? And even then it was really only on TO. It was all about supersonic being no different than the norm. There's a famous quote re one of the test flights/demos about something like (and I'm paraphrasing): 'it's not extraordinary' and 'yes, that was the hard part!'.


That was from George Edwards, 'the hard part' the then head of BAC.
 
Tristarsteve
Posts: 3729
Joined: Tue Nov 22, 2005 11:04 pm

Re: Concorde time spent at max thrust with full reheat

Thu Jun 30, 2022 6:15 pm

Everyone is commenting on how normal the Concorde noise was inside, lets not forget it was very noisy outside. On the occasion of Gatwick airports 50 anniversary, BA substituted a Concorde on some B737 flights out of the airport.
One came to me at ARN, and I was the local engineer organising it all. A ground engineer arrived on the aircraft, but he refuelled it, and it took all of the hour we had to put fuel in all the tanks, even for the short flight to LGW.
So in the end I put on the headset and we started it up. Two Air start units, one each side,(no cross bleed air duct) and soon two engines were running, and I could hardly hear myself think. Then I asked the Flight Engineer if we could remove ground power, NO he said, we are going up to ground idle first, and the noise level on the ramp got a lot louder.
So we finished the push back, disconnected the towbar, and I removed the Concorde adaptor from the B747 towbar we had used. The R1 door opened and a rope came down, which I tied the adaptor to and it was hoisted up into the aircraft ready for the next station.

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