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Subsonic Flights - Is 55% CG always the rule?


Ray Proudfoot

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Fraser Gale

Just for the other record, minimum fuel policy at BA was 25T subsonic sector 35T supersonic sector. 

As has been said, things were done differently on either side of the channel and it's one of the reasons there was very little exchange between the airlines although I know that attempts were made. Remember that company rules are applied on top of manufacturer rules and in BA, a lot of the early work was done by captains who flew her, especially noise abatement techniques and planning. All the manuals were originally written by the "nucleus group" of pilots while they were carrying out the route proving. It is because of this there is bound to be differences which I am interested in learning about on here I must say, so thanks Fabrice for your input. 

I will however, for the benefit of those who ask me questions, stick with what I know and that is BA policy. 

Frazz

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Ray Proudfoot

Hi Fabrice,

Thank you for your input for the EGLL-EIDW flight. I've overwritten that flight report with one for 100 pax and of course my FL was either 260 or 280 so way too low which resulted in less fuel on landing than CPS-X calculated.

I'll generate a new report tomorrow with 100 pax and report back with fuel used plus ZFW etc.

Hi Frazz, thanks for the document, much appreciated. :)

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Pierre Chassang
9 hours ago, Ray Proudfoot said:

Hi Fabrice,

Thank you for your input for the EGLL-EIDW flight. I've overwritten that flight report with one for 100 pax and of course my FL was either 260 or 280 so way too low which resulted in less fuel on landing than CPS-X calculated.

I'll generate a new report tomorrow with 100 pax and report back with fuel used plus ZFW etc.

Hi Frazz, thanks for the document, much appreciated. :)

Ray,

CPS-X calculates fuel in accordance to the user entered FL, not to optimal FL.
This might be the subject of a future improvement.

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Ray Proudfoot
1 hour ago, Pierre Chassang said:

Ray,

CPS-X calculates fuel in accordance to the user entered FL, not to optimal FL.
This might be the subject of a future improvement.

Sounds good. CPS-X knows the distance of the supplied route so it shouldn't be too difficult to advise the optimum FL.

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Fraser Gale

The specific distance is used on the re-planning tables in the BA documents along with time and fuel but I think they thought it was clearer to keep optimal flight level separate because it is dependant of weight. Interesting to see the different methods however.

Frazz

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Pierre Chassang
2 hours ago, Ray Proudfoot said:

Sounds good. CPS-X knows the distance of the supplied route so it shouldn't be too difficult to advise the optimum FL.

There is no need knowing the distance, (TOW + LDGW) / 2, could be used to calculate the average optimal FL.

Adding this in the to do list.

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Fraser Gale

The above formula would work for a rough guide but the optimum flight level is not a straight line graph and is therefore a little more complex than that. Also remember that this only works for subsonic only sectors and the calculations for supersonic optimums are different.

Frazz

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Pierre Chassang
2 hours ago, Fraser Gale said:

The above formula would work for a rough guide but the optimum flight level is not a straight line graph and is therefore a little more complex than that. Also remember that this only works for subsonic only sectors and the calculations for supersonic optimums are different.

Frazz

Of course Frazz...

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Ray Proudfoot

Just completed EGLL-EIDW. TOW=116.9T, Landing Weight = 105.7T. Fuel Loaded 25.6T. Cruise at FL330 / M0.95.

The Mach Hold command above AT1/2 doesn't appear to work. I selected it as the aircraft climbed towards FL330 expecting it to hold at M0.95 but it didn't. I had to switch to IAS ACQ and adjust that way. Just added to the already high workload.

Anyway, I landed with 14.3T and CPS-X estimated 14.9T so that's reasonable I suppose. I didn't fly the STAR, just direct to the waypoint on the localiser at LAPMO.

I suspect the fuel needs tweaking in Concorde. I've seen a few other comments about its subsonic fuel consumption.

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Pierre Chassang
55 minutes ago, Ray Proudfoot said:

Just completed EGLL-EIDW. TOW=116.9T, Landing Weight = 105.7T. Fuel Loaded 25.6T. Cruise at FL330 / M0.95.

The Mach Hold command above AT1/2 doesn't appear to work. I selected it as the aircraft climbed towards FL330 expecting it to hold at M0.95 but it didn't. I had to switch to IAS ACQ and adjust that way. Just added to the already high workload.

Anyway, I landed with 14.3T and CPS-X estimated 14.9T so that's reasonable I suppose. I didn't fly the STAR, just direct to the waypoint on the localiser at LAPMO.

I suspect the fuel needs tweaking in Concorde. I've seen a few other comments about its subsonic fuel consumption.

Remember, CPS-X has a fuel bias setting...

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Ray Proudfoot
13 minutes ago, Pierre Chassang said:

Remember, CPS-X has a fuel bias setting...

I thought that was for FS9? Presumably it affects all flights including supersonic ones.

I would need to tread very carefully. Has anyone else tweaked this?

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Fraser Gale

Personally I would have engage Mach hold on the autopilot in order to use full power to climb as quickly as possible, with the AT engaged in standby to take over on the alt aquire sequence. You are correct though Ray, the Mach hold leaves a lot to be desired at times - clearly the accelerometer inputs have hot been simulated like they would have been on the A320!

Frazz

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Ray Proudfoot

I did try MAX CLB briefly but with such a short flight and light fuel load it was climbing at over 8000fpm. I decided that wasn't very good for the pax.  Also, the CG was going aft faster than the pumps could cope.

Hopefully @Andrew Wilson will have some time soon to tidy up the few remaining bugs like MACH HOLD on the AFCS not working. :)

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Fraser Gale

To be honest, on most of these flights in real life the handling pilot would probably have hand flown most of it but then he had two others to help him/her out! 

It was common practice to start the fuel moving aft early on lightly loaded flights to anticipate the CG change. As much as 8000ft/min sounds scary, this would have been tolerated on the line as it did happen occasionally when flying down in the tropics on the Singapore route for example. A Concorde captain once told me of an occasion when he was asked to take a Concorde from Heathrow to Edinburgh and back to fly the shuttle service - this happened more than once by the way. He said the first officer was doing the flying and they decided to go supersonic over the North Sea, they accelerated off the Thames estuary climbing at a rather high rate (the aircraft was light obviously) they switched off the reheats at 1.7 expecting things to calm down but they didn't! She just kept climbing with the FO hand flying he pointed out that the would soon reach 60000ft but the captain said he advised him to level off and throttle back slowly, partly for PAX comfort and partly to avoid surges, with the result that he said they got to around 63000ft before bringing her back to normal! 

Needless to say I don't think they'd have been popular back at base!

Frazz

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Ray Proudfoot

That's a tremendous story and thanks for sharing. Mine was all on autopilot I'm afraid as my Saitek yoke isn't quite as good as Concorde's. :D Plus I had to do the job of the FE but no comms so just the work of two!

I'm surprised they were able to climb to 630 in these latitudes. I thought that was only possible in the tropics but perhaps the light load made it possible.

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Fabrice Estienne

Roger, Ray, I will try the flight with along 100 pax, FOB 25 t and the engine control schedule checked on Flyover.

Will go back over very soon.

Cheers

Fabrice

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Pierre Chassang
20 hours ago, Ray Proudfoot said:

I thought that was for FS9? Presumably it affects all flights including supersonic ones.

I would need to tread very carefully. Has anyone else tweaked this?

Fuel bias can be used with any simulator...

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Ray Proudfoot

Just completed another test flight EGLL-EIDW. TOW=116.2, Landing Weight 104.9. Fuel loaded 25.7T. Fuel remaining 8.9T compared to 15.0T calculated by CPS-X. :(

Now whilst the Total Fuel Contents above Engine 4 N2 shows 8900 the fuel remaining on the engineer's panel is 13.9T. But my EFB Flight Log shows 9061.3Kg on landing so that is the correct amount of fuel. I don't think the engineer's panel is accurate.

I did a couple of things differently in this flight. Used Flyover mode once airborne and engaged VERT SPD mode so I could better control speed. Mach 0.95 was achieved pretty much throughout the cruise mode.

Started down 21nm before ABLIN with 350kt IAS and throttled back to near idle. Achieved FL100 39nm from the DAP VOR. This is just west of Rwy 10/28.

Slowed to 250kts and descended to 3000 by LAPMO. Turned onto the localiser at 200kts (bit fast I know) and landed manually.

Compared to yesterday the fuel used was significantly higher. Only real change was using Flyover mode. Does that eat more fuel? I can't think of any other reason for the high fuel burn.

Weather was AS16 in Live Mode.

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Fraser Gale

Flyover mode reduces fuel burn (in real life anyway!) by better matching of N1 and N2 during subsonic cruise as well as reducing noise after takeoff which is why it is pre-selected before takeoff and left selected until the acceleration checks. 

Seems strange that you should get very different fuel quantities. 

Frazz

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Ray Proudfoot

Yes, strange indeed. I look forward to hearing how Fabrice got on. There was a couple of hours between me generating the data with CPS-X and flying it. Can't imagine the wx changed that much. :(

I might switch back to Normal mode and see what difference it makes. I can compare fuel used at each waypoint with my EFB Logs.

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Ray Proudfoot

One final test flight completed. TOW = 115.5T, LW = 105.4T. Fuel Loaded 25.5T, Fuel on landing 12.7T. CPS-X calculated 14.8T.

One change from before, FL340 as advised by CPS-X. In all other respects descent was identical to previous one.

That's closer to my first test and also not using Flyover. I think I'll stick to Normal mode and add a Fuel Bias around 12% to CPS-X. Another test tomorrow.

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Fabrice Estienne

Just achieved a flight test.

100 pax, FOB 25 t, TOW 113 t.

The INS refused to work in NAV mode, what's really strange they work when on LFPG !; hence I decided to fly VOR to VOR.

Was not able to manually execute the trim transfer by this blasted TRIM TRANS AUTO MASTER control lever. Used the FVE.

After CPT I simulated a clearance to FL350 to reach the optimum level at M.95 (330 kIAS at FL350).

Noticed that the VMO barber is inaccurate when the GW is below 165 t; in this particular case the VMO is computed by the ADCs according the altitude and the GW. FSL did not process this matter if I am not mistaken.

I changed the flight level by mean of IAS mode of the AP.

Finally I simulated a about 30 minutes Holding at 205 kt before a vectoring ILS 28 .

On ground on Rwy 28 EIDW : GW is  93.7 t hence 19.3 burned.

Regards

Fabrice

 

 

CC_Rwy27R_EGLL.PNG

CC_10NM_before_CPTL.PNG

CC_64NM_before_DUB_M.95_FL350.PNG

CC_Final_Rwy28_EIDW_After_Holding_Fuel_6700kg.PNG

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Ray Proudfoot

Thanks very much Fabrice. Can you estimate your fuel remaining before you went into the hold at EIDW? That will use quite a bit of course.

What was your heading after CPT? Direct to EIDW?

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Fraser Gale

Fabrice, can I ask how you calculated your final approach speed? It is low even for a very light aircraft as you were. It looks like you were using the lowest authorised Vref which is legal but it was standard practice to add on 7 knots to Vref to give Vtt - the aircraft was easier to handle and it normal assists in a smoother touch down.

Also, if you are flying a reduced noise approach (as was always the case unless you had certain failures) you would fly at 190kts until the 800ft radio call, when you would select IAS ACQ to reduce to Vtt - which would be preselected in the window. Also, both autothrottles are engaged at all times except when the AFCS is in MAX CRUISE mode, this provides a monitoring backup. 

Just some little tips and hints to aid your Concorde enjoyment!

Frazz

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Ray Proudfoot

One small issue about fuel in tanks 9 and 11. When I'm close to ToD there is still fuel in 9 and more than the amount calculated by CPS-X for landing. What I'm doing as the descent starts is to pump the excess from 9 to 11. Clearly this results in the CG moving rearwards to around 55.2.

Once the correct amount is in 9 I then reverse the pumps and move fuel from 11 into 5 and 7 from where it is fed to the four main collector tanks.

Landing CG is forward of 53%. Is that the correct way to do it?

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Fabrice Estienne

Good evening Ray + Frazz

FOB at Take-Off : collectors 1-4 full, tank 9  5040 kg and tank 11  1890 kg aiming to a 53 % MAC (TOW < 140 t and TOW-LW > 7t).

Landing CG, yes 53%, aft  threshold 53.5% and of course except Re-Land conditions.

If I have a memory of: 11 400 kg before holding and one should take in account the ILS procedure.

Did not take in account a reduced noise approach, nevertheless I agree that Frazz is right: VTT= VLA + 0 Wind + 7 kt.

My approach speed assistant which replaces the standby ASI / Machmeter of the CPT dash panel does not anything if I proceed a reduced approach.

As regards the engine parameters in cruise M.95 / FL350 they are noticeably outside of the cruise tables (AF documentations)

AF tables ISA 102 t, M.95/FL350: N2=85.70 %, FF= 2590 kg/h (by interpolation) and CC FSL : N2=93%, FF=3900 kg/h

I fly her under a modified FSX / P3D sim which enables a genuine and accurate anemometric model. This is the reason why you can see various speeds added in the bird simulation.

Cheers

Fabrice

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Fabrice Estienne

Ray,

If i have remember of I took a heading of 345 (the first one that came to hand !) after CPT to intercept DUB then intercept DAP.

I must admit I did not prepare my flight in a very professional way...

Cheers

Fabrice

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Fraser Gale

Ray, if you still have fuel in tank 9, the best thing to do is manually open the inlet valves to 5 & 7 and switch on the pumps in 9 (and 11 if you wish)  to move the fuel without major CG impact.

Fabrice, the latest version of Concorde has some serious glitches with the N1/N2/FF values, and in fact on takeoff I often see an N2 of 108% which is above the limits for the engine. 

Frazz

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Ray Proudfoot
58 minutes ago, Fabrice Estienne said:

Ray,

If i have remember of I took a heading of 345 (the first one that came to hand !) after CPT to intercept DUB then intercept DAP.

I must admit I did not prepare my flight in a very professional way...

Cheers

Fabrice

Hi Fabrice,

You cut the corner after passing CPT. ;) Here is the plan I flew...

CPT UL9 KENET UN14 OKTAD DCT MEDOG UL18 LANON DCT ABLIN DCT LAPMO

That's parked at Terminal 4, stand 425 with a 27L departure and landing on Rwy 28 with no speed restriction out of EGLL and no holding at EIDW.

Could you fly that route at FL330 please and see how it goes? What's your fuel remaining after landing?

I'm flying FSX:SP2. What sim are you flying?

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Ray Proudfoot
58 minutes ago, Fraser Gale said:

Ray, if you still have fuel in tank 9, the best thing to do is manually open the inlet valves to 5 & 7 and switch on the pumps in 9 (and 11 if you wish)  to move the fuel without major CG impact.

Frazz

Thanks Frazz. makes sense.

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Fabrice Estienne
8 hours ago, Ray Proudfoot said:

Hi Fabrice,

You cut the corner after passing CPT. ;) Here is the plan I flew...

CPT UL9 KENET UN14 OKTAD DCT MEDOG UL18 LANON DCT ABLIN DCT LAPMO

That's parked at Terminal 4, stand 425 with a 27L departure and landing on Rwy 28 with no speed restriction out of EGLL and no holding at EIDW.

Could you fly that route at FL330 please and see how it goes? What's your fuel remaining after landing?

I'm flying FSX:SP2. What sim are you flying?

Hi Ray,

Today I fly FSX SP2 enhanced with a new anemotric model which does not influence any add-ons, hence Concorde-X.

Only the CAS displayed by the ASI and the Barber Pole (VMO) in certain occasion (if I trigger the relevant option) may differ from those shown to the pilots in Concorde-X.

Will fly your FPL with both no speed restriction above FL100 and no altitude restriction at CPL (actually not above 6000 ft), do you confirm ?

Will Cruise at FL330 and I will trace the fuel.

Cheers

Fabrice

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Ray Proudfoot

Hi Fabrice,

So we have the same version of FS although it sounds like you have a anemotric model which I confess I have never heard of. But it sounds like the differences are not major.

I will restrict my speed to 250kts below FL100 (even though that was often lifted in real life). Confirm no altitude restriction at CPT.

Can you confirm the time the reheats are on for? I have 69 seconds which I think is too long for such a light load. That will use a huge amount of fuel so perhaps we should agree to the same time?

Thanks for your help. :-)

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Fabrice Estienne

Hi Ray,

I added myself a code to FSX / P3D to provide accurate speeds (especially IAS / CAS). I was fed up with unconventional speed shown to the pilots. In particular above M1 FSX and P3D (both originated from Microsoft ESP platform) provide absolute nonsense with the Indicated Air Speed (IAS). The deviation may reach up to 120 kt at M1.8 at sea level and at M2 / FL530 the difference is about 45 kt. More the IAS computation of FSX / P3D does not consider that the ADC / ADR of CS25 / FAR25 aircraft adjust the measurement of the airflow according the AOA. For your perfect information I requested Lockheed Martin to make the correction into the sim core.

That aside the others features are unchanged.

I do not use the reheats since looking at the TOW of Concorde + the EGLL runways 27 are not restrictive, that I gauge.

By the way could you send me your EGLL to EIDW.AWC file to be absolutely sure I fly the same FPL.

Cheers

Fabrice

 

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Ray Proudfoot

Hi Fabrice,

You are more of an expert than I could ever imagine. :D

I planned on reheats for 30s but I will not use them so we have the same conditions.

FSLabs don't allow any uploads however small. Here are the two files. Please save as EGLL to EIDW.1.AWC and EGLL to EIDW.2.AWC

; ADEU card for: EGLL to EIDW
; Departure: EGLL
; Destination: EIDW
; Part 1
1 N 51*29.5 W 001*13.2 ; CPT
2 N 51*31.2 W 001*27.3 ; KENET
3 N 51*49.1 W 002*32.8 ; OKTAD
4 N 51*57.0 W 003*33.0 ; MEDOG
5 N 52*25.9 W 004*22.3 ; LANON
6 N 52*47.0 W 004*59.5 ; ABLIN
7 N 53*24.2 W 005*56.7 ; LAPMO
;; End Of File;
; File generated by CPS.

; ADEU card for: EGLL to EIDW
; Departure: EGLL
; Destination: EIDW
; Part 2
8 N 53*25.3 W 006*16.2 ; EIDW
;; End Of File;
; File generated by CPS.

I'm about to fly it with TOW 115.7, Pax=100, FL340. Rwy 27L and 28.

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Fraser Gale

Reheats were always used to the point that BA pretty much removed the "Takeoff Without Reheat" procedure from the performance manual. For a weight of 130 tonnes or lower on 27L with a temperature of 15C the noise time is 48 sec TLA is 23.0 with N2 of 89.9%

Remember the object of the noise procedure was to climb as high as possible before throttling back to the lowest power possible, hence reheat used to accelerate quickly and climb quickly. This is why she was quieter with lighter loads. 

If you are going to takeoff without reheat your PLTOW must be reduced by 25%, V1 reduced by 20kts and Vr/V2 reduced by 25kts. 

The noise speed is also reduced to 225kts instead of 250kts. You also have to add 8 secs to throttle time, subtract 1 degree from TLA and add 1.5% to N2 value. 

Frazz

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Ray Proudfoot

Cheers Frazz. Did you remember all that from memory or did you have to look it up? :D

I think in future I will use reheats for the reason you mention. Get high quickly!

Just finished my latest test and the results are baffling. With Fuel of 25.7T; 100 pax; TOW = 115.7T I landed at Dublin with 9.7T remaining. CPS-X calculated 14.8T. :huh: I had 14.7T remaining at OKTAD with 173nm still to fly.

I'm looking forward to seeing Fabrice's results.

Comparing this flight (no reheat and 250kts below FL100) with my previous one (reheat and no speed restr) these are the numbers at CPT. Reheat flight in bold...

CPT Alt/Speed = 16400/487 (14400/479); Fuel Remaining = 19115Kg (21498Kg)

At MEDOG FL340; Fuel Remaining 13732Kg (16874Kg). MEDOG is the half-way point.

After Landing 9673Kg (12601Kg)

Not using reheat on take-off ends up with more fuel being burned overall. :wacko:

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Fraser Gale

In some ways that makes sense to me - a lot about Concorde is backwards especially in the subsonic regime where everything is a compromise. However, I think it's widely known that the physics of FSX/P3D are not exact science, and although I know nothing about how Concorde X was coded, in my experience the subsonic numbers are not brilliantly accurate, although I could be wrong here. On long distance supersonic segments the numbers are within cruise control manual data for planning. 

What is different here is that when planning properly time is used, not distance. For example, if you have an aircraft weight of 115T the time allocated to take-off and climb to 1000ft is 1min with fuel of 900kg. If there is no noise procedure the time is 2mins and 500kg - this is a reheats off at 1000ft continuos climb departure.

In ISA conditions, climb to FL330 would be: 9mins, 4000kg, TAS 424kts - note this is for full performance climb to VMO with noise procedure.

Subsonic cruise at FL330 with a start weight of around 110T would give a fuel flow of 10600kg/HR which you would then have to divide by 60 and multiply by the number of minutes you plan to be in the cruise. 

Descent would be: 10mins, 1550kgs, TAS 410kts with a distance covered of around 67NM in still air. 

6450kgs plus the cruise segment which I would need the time for. 

Perhaps you could use the above figures to work out how much fuel you would expect to use in cruise by calculating how long the cruise segment is, then we will have something official to compare it all with? 

Let me know what you calculate. 

Frazz

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Ray Proudfoot

Frazz,

My start weight was 115.7T and looking at the EFB Flight Log it took 10-11 minutes to reach FL330. Now as we know Mach Hold does not work so I had to adjust the IAS ACQ to maintain M0.95 and that meant the speed did vary by +/- 0.03 or so. Weight at start of cruise was 115.7 - 10.4 = 105.3T.

I estimate I was at cruise for 10 minutes after which I started a standard Concorde descent at 350kts at idle power. It took 11 minutes to descend to 4000ft / 250kts which covered around 65nm.

I used a total of 13.3T of fuel from pushback to landing (not taxiing to gate). The distance flown was 256nm and it averaged 38 minutes.

I hope that gives you something to work with but if not here's the EFB log that contains all the info above.

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When conducting subsonic flights with Concorde-X, please keep in mind that the fuel burn figures differ significantly from the real-world values. As I described in this thread, the engines in Concorde-X burn over 1000 kg/h more fuel per engine than the former real-world pendant at any weight and flight level. If your subsonic flight lasts e.g. four hours, it can consume 16 tons more of fuel overall, which is equivalent to one hour of additional flight time.

If you are interested, you can try my modified Concorde.air-file and FuelBurn.ini-file, where I have corrected the subsonic fuel consumption (it still consumes slightly more than the real-world thing, but the deviation is only in the magnitude of roughly 100 - 250 kg/hr/e). 

[UPDATE Apr-10-2017: The files have been updated to the newest version. Please refer to the following thread for more information:]

http://forums.flightsimlabs.com/index.php?/topic/12598-modified-concordeair-and-fuelburnini-files-for-more-accurate-subsonic-fuel-consumption/

 

 

 

 

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Ray Proudfoot

Thank you very much afterburner. :D I was going mad trying to work out why my flights were consuming so much fuel whatever steps I took to keep as close as possible to real-world ops.

Having read that thread it's encouraging that Andrew wants to further improve the fuel burn. Hopefully he'll find the time soon. But in the meantime I'll certainly use your alternative files after backing up my originals first of course.

I also think anyone planning to fly sub-sonically with Concorde would benefit from these especially if they're going to use CPS-X. @Pierre Chassang, is it worth mentioning these files in the CPS-X release notes?

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Fabrice Estienne

Hi again Ray + Frazz

pax 100, crew 9, FOB 25 t, TOW 113.6 t.

INS refused to steer the bird to CPT, then KENET, then OKTAD, but forced the flight directly to MEDOG.

TO with no reheats, climb around the target 338 kIAS (CC_flyover_CPT).

DCT MEDOG.

Cruise at FL340 / M.95 / 338 kt (CC_flyby_MEDOG)

TOD at 120 NM DAP.

Vectoring ILS 28 (CC_Final_Rw28).

On ground with 102.5 t

Burned fuel 11.1 t.

Cheers

Fabrice

 

 

 

CC_flyover_CPT.PNG

CC_flyby_MEDOG.PNG

CC_Final_Rw28.PNG

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Ray Proudfoot

Thanks Fabrice. Interesting fuel burn of 2.2T less than mine. Do you use afterburner's modified air file and fuelburn.ini by any chance?

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Fraser Gale

Fabrice,

interesting results although I'm curious to know if AF used a different climb technique to BA? Did they not climb at VMO? 

Also, did they not use both autothrottles as a safety feature?

Frazz

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Fraser Gale

Afterburner, what would be good is if we had a full fleet modelled (I know you can download them from here although I couldn't get them working) with slightly different fuel burns for each one as per the real aircraft. G-BOAD was regarded by many of the crew as the best in the fleet because she burned less fuel, if I remember correctly G-BOAF was a close second because she was the lightest, G-BOAC was heavy compared with most and had one wing heavier than the other because of a repair that had to be done. One captain told me his least favourite was G-BOAE because it felt "sloppy" to fly and he felt it was harder to keep in the slot on approach - this could be subjective though! Although, on the last day of service it was 'AE that had a dodgy radio after landing...

Frazz

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