Board index FlightGear Development Aircraft Cockpit development

Concorde cockpit redesign

Discussion about creating 2d and 3d cockpits.

Re: Concorde cockpit redesign

Postby V12 » Fri Nov 23, 2018 7:13 pm

My descent procedure is not realistic, but works well :
- deceleration point is calculated for descent at 4000 fpm from cruise level to FL100
- at deceleration point set speed to 250 KIAS, click on AA, select vertical speed 4000 fpm
- at FL100 wait for speed 250 kts, then proceed descent with old known rule - for 3000 feets of altitude You will need 10 nm of distance, add correction for headwind/tailwind
- approach speed minimum 200 KIAS, on short finale can be 170 KIAS, touchdown speed 162 KIAS for 20 tons of FOB
- touchdown with max 11 degs pitch, hold this pitch as long as You can, large delta will serve as giant airbrake
- for short runway use reversers immediately after touchdown
- for even shorter runway (under 2000 meters) activate reversers in airborne (will be active only 2), after touchdown reapply reversers for use all 4, You should full stop on 1500 meters long runway :) Not realistic procedure, but usable at Merida (SVMD) or Stord (ENSO) :twisted:
Fly high, fly fast - fly Concorde !
V12
 
Posts: 2757
Joined: Thu Jan 12, 2017 5:27 pm
Location: LZIB
Callsign: BAWV12

Re: Concorde cockpit redesign

Postby legoboyvdlp » Fri Nov 23, 2018 11:08 pm

Quick question,
It felt like the Concorde was too light. I was about 85T, fairly near max fuel, all tanks full but 11 and 9. I reached FL600 easily. IRL apparently it would only reach about 510 and then cruise climbed to 600? 600 was the max ceiling, right? I felt like I could make 700!

Maybe it is because maybe you can add only fuel, not passengers?

Or maybe something in jsbsim or the atmosphere changed so drag is different...?


And one more question, where can you adjust the vertical speed in the 3D cockpit?
User avatar
legoboyvdlp
 
Posts: 7981
Joined: Sat Jul 26, 2014 2:28 am
Location: Northern Ireland
Callsign: G-LEGO
Version: next
OS: Windows 10 HP

Re: Concorde cockpit redesign

Postby V12 » Sat Nov 24, 2018 12:54 am

Andre Turcat reached easy FL680, limit was only his courage. It was on french prototype. Production planes had bit powerfull engines than prototypes. Another his test - reached maximum speed M2.23 (or M2.27 ? I'm not absolutly sure), again, limit was courage.
Original fgaddons Concorde has not speed limit, I made M8 and plane still accelerated. And altitude has hardcap at 103k feets, if I remember correctly. That performance was unacceptable, I changed engine parameters to set limits near Turcat's values. Meassured thrust 10000 lbs at FL510 and M2.04 was unchanged. Empty operational weight (without fuel, pax, crew and cargo) should be 78.7 tons. Official max range was 3700 nm, but in optimal metheo condition Concorde was able fly from SVMI to LFPG - 4100 nm. This was possible only in case of ignore 250 kts restriction under FL100 and climb to FL600 as fast as possible, not with cruise - climb style.
FG probably has not very accurated high altitude atmosphere model, over FL500 is constant -56 degs C. But in reality temperature shoul be bit higher, then Total Ram temperature at aircraft's nose is higher and plane must slow down. Tmo limit vas 128 degs C, what was M2.04 (in FG for Tmo 128 degs C You obtain M2.06).

EDIT :
I checked http://www.concordesst.com/weight.html

Max Weight Without Fuel (Zero fuel weight) 203,000 lbs (92,080 kgs)
Operating Weight Empty 173,500 lbs (78,700 kgs)
Max Payload 29,500 lbs (13,380 kgs)
Max Take Off Weight 408,000 lbs (185,000 kgs)
Max taxing Weight 412,000 lbs (186,880 kgs)
Max Landing Weight 245,000 lbs (111,130 kgs)
Max Weight of Fuel 26,400 gallons <=>95,680 kgs
Max baggage weight (under floor hold : forward of door) 2,194 lbs (995 kgs)
Max baggage weight (under floor hold : aft of door) 1,290 lbs (585 kgs)
Max baggage weight (Rear Hold : Lashed) 6,100 lbs (2,767 kgs)
Max baggage weight (Rear Hold : Un-Lashed) 5,000 lbs (2,268 kgs)

In FG, Concorde is configured for maximum pax and maximum cargo, ZFW is around 203000 lb.
Fly high, fly fast - fly Concorde !
V12
 
Posts: 2757
Joined: Thu Jan 12, 2017 5:27 pm
Location: LZIB
Callsign: BAWV12

Re: Concorde cockpit redesign

Postby V12 » Sun Nov 25, 2018 12:24 pm

And here is vertical speed control :

Image

In the red square is lever for tuning vertical speed, this control is active only in V/S mode on autopilot.
Fly high, fly fast - fly Concorde !
V12
 
Posts: 2757
Joined: Thu Jan 12, 2017 5:27 pm
Location: LZIB
Callsign: BAWV12

Re: Concorde cockpit redesign

Postby legoboyvdlp » Sun Nov 25, 2018 4:33 pm

Thank you!
User avatar
legoboyvdlp
 
Posts: 7981
Joined: Sat Jul 26, 2014 2:28 am
Location: Northern Ireland
Callsign: G-LEGO
Version: next
OS: Windows 10 HP

Re: Concorde cockpit redesign

Postby V12 » Tue Nov 27, 2018 6:39 pm

legoboyvdlp wrote in Fri Nov 23, 2018 11:08 pm:Quick question,
It felt like the Concorde was too light. I was about 85T, fairly near max fuel, all tanks full but 11 and 9. I reached FL600 easily. IRL apparently it would only reach about 510 and then cruise climbed to 600? 600 was the max ceiling, right? I felt like I could make 700!

Maybe it is because maybe you can add only fuel, not passengers?

Or maybe something in jsbsim or the atmosphere changed so drag is different...?


I tested more realistic engine settings, but weather discontinuity can ruin Your flight at edge on the flight envelope - engines will have not enough power to compensate sudden wind speed and direction changes, baro pressure is changing in steps too. This phenomena is described at viewtopic.php?f=69&t=33893&hilit=discontinuity
Fly high, fly fast - fly Concorde !
V12
 
Posts: 2757
Joined: Thu Jan 12, 2017 5:27 pm
Location: LZIB
Callsign: BAWV12

Re: Concorde cockpit redesign

Postby Thorsten » Tue Nov 27, 2018 7:38 pm

baro pressure is changing in steps too.


Unless you're referring to framerate as 'steps' (which brings to the truism that the simulation runs in discrete timesteps, no nothing ever changes really continuously) - no, it's not. It's always interpolated in time, i.e. ramped to a new target value over a finite time (as I already explained).

Real APs have to deal with windshear, turbulence and instrument noise just as well - AP designers in FG just have to work a bit harder. If I can write an AP which takes a lot of crap, so can you.
Thorsten
 
Posts: 12490
Joined: Mon Nov 02, 2009 9:33 am

Re: Concorde cockpit redesign

Postby V12 » Tue Nov 27, 2018 9:31 pm

OK, why barometric altimeter suddenly hop 1000 feets when active metar station change occurs ? This is reality in FG at long flight over ocean, where the distances between metar stations are real large, more than 300 nm...
Fly high, fly fast - fly Concorde !
V12
 
Posts: 2757
Joined: Thu Jan 12, 2017 5:27 pm
Location: LZIB
Callsign: BAWV12

Re: Concorde cockpit redesign

Postby Thorsten » Tue Nov 27, 2018 9:51 pm

If you feel some input value is changing too fast, simply pass it through an averaging filter before using it in the AP.
Thorsten
 
Posts: 12490
Joined: Mon Nov 02, 2009 9:33 am

Re: Concorde cockpit redesign

Postby V12 » Fri Dec 28, 2018 9:19 pm

I played with FSX's freeware version of the Concorde, cruise climb worked perfectly. Then I found editor for .air files. I will try extract thrust/alt/speed data for fine tuning engine performance to obtain as realistic behaviour as I will can do.
Fly high, fly fast - fly Concorde !
V12
 
Posts: 2757
Joined: Thu Jan 12, 2017 5:27 pm
Location: LZIB
Callsign: BAWV12

Re: Concorde cockpit redesign

Postby Octal450 » Sat Dec 29, 2018 6:58 am

I'm sorry, don't bother with it. FSX freeware models usually have very poor flight models. If you want to crosscheck against another, maybe crosscheck against videos of the FSLabs ConcordeX? Its probably alot closer.

Kind Regards,
Josh
Skillset: JSBsim Flight Dynamics, Systems, Canvas, Autoflight/Control, Instrumentation, Animations
Aircraft: A320-family, MD-11, MD-80, Contribs in a few others

Octal450's GitHub|Launcher Catalog
|Airbus Dev Discord|Octal450 Hangar Dev Discord
User avatar
Octal450
 
Posts: 5583
Joined: Tue Oct 06, 2015 1:51 pm
Location: Huntsville, AL
Callsign: WTF411
Version: next
OS: Windows 11

Re: Concorde cockpit redesign

Postby V12 » Sat Dec 29, 2018 7:53 am

You should be right, but actual setup in FG is wrong - with 75 tons FOB and full pax You can easy climb to FL600 because Aeromatic estimate too large ram recovery over 1.3M. Afterburners efficiency is wrong too, in some situation You obtain 80% more thrust than in the reality. That freeware models nice simulated cruise-climb...
I found many videos with FSL Concorde, cruise climb is again perfect. And there is another problem - FG doesn't use wind aloft and vertical temperature profile. Static temperature above FL360 is fixed to -57 degC around all globe. In FSX I encountered -67 degC over equator. Solution is simple - I will add some kN of the thrust, because in ISA+O and real 10000 lbs at FL530 and M2 the plane can't reach FL530. But with 12500 can.
Fly high, fly fast - fly Concorde !
V12
 
Posts: 2757
Joined: Thu Jan 12, 2017 5:27 pm
Location: LZIB
Callsign: BAWV12

Re: Concorde cockpit redesign

Postby V12 » Sat Dec 29, 2018 1:54 pm

I found that actual thrust tables are not from aeromatic. Working on new parameters, FSX's params are not usable, because different FDM.
Fly high, fly fast - fly Concorde !
V12
 
Posts: 2757
Joined: Thu Jan 12, 2017 5:27 pm
Location: LZIB
Callsign: BAWV12

Re: Concorde cockpit redesign

Postby V12 » Sun Dec 30, 2018 4:34 pm

After many trials (and errors) I found setup that simulates engines more realistic than previous version. After take off with MTOW plane reach FL500 with remaining 75 tons FOB and continue climb maximum 100 fpm. I need test this new setup on more geographical location.

EDIT :
Tested on route from LPMA to LZIB (https://fgtracker.ml/modules/fgtracker/ ... ID=7073776). Engine parameters looks good, but I found AP limitations :
- improperly implemented Max Climb
- strange Max Cruise mode
- strange implemented climb with MACH hold, but climb with IAS hold works good

Standard flying style (climb to defined flight level) is ofcourse possible, but range is limited. Other solution is climb to FL500, then set ALT to 60000 feets, engage ALT Acquire with V/S speed 50-60 fpm, this should nice simulate Cruise - Climb, because FG atmosphere temperature above tropopause is pretty static -57 degC. I have some ideas, how to make Max Cruise mode.

Concorde's autopilot needs general revision, but my knowledge about AP programming is not enough to allow me do that revision :(
Fly high, fly fast - fly Concorde !
V12
 
Posts: 2757
Joined: Thu Jan 12, 2017 5:27 pm
Location: LZIB
Callsign: BAWV12

Re: Concorde cockpit redesign

Postby V12 » Mon Dec 31, 2018 7:08 pm

I compared roll rate and pitch rate of FG Concorde and FSX Concorde from XXXX developer. And found :
FG roll rate for full barell roll 7 seconds, FSX 15 seconds
Pitch rate from 0 deg to 40 degs 2 seconds, FSX 5 seconds

Test with 40 tons FOB, 250 kts at 5000 feets.

Result - I must do something with elevon's efficiency, or inertia momentum :(
Last edited by V12 on Mon Dec 31, 2018 7:09 pm, edited 1 time in total.
Fly high, fly fast - fly Concorde !
V12
 
Posts: 2757
Joined: Thu Jan 12, 2017 5:27 pm
Location: LZIB
Callsign: BAWV12

PreviousNext

Return to Cockpit development

Who is online

Users browsing this forum: No registered users and 1 guest