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Old 11-03-2012, 09:40 PM   #21
Anaraxes
 
Join Date: Sep 2007
Default Re: [3e] F-111

The number you want to correlate to sustained maneuverability is probably "wing loading". An instantaneous G-rating measures airframe strength, but what matters is how fast the airplane loses its energy as it maneuvers. Two planes might both pull 6G, but the one with higher wing loading is losing more energy to do so. The opposing factor is the power of the engines, which add energy to the plane. Given two planes with the same wing loading, the one with more powerful engines will be able to keep up the dogfighting longer.
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Old 11-04-2012, 01:27 AM   #22
Pomphis
 
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Default Re: [3e] F-111

Quote:
Originally Posted by Phaelen Bleux View Post
Well, in that case the materials have a lot more to do with the stealth technology of the F-22.
In RL, yes. In VE2 terms at TL7 Radical Stealth adds $ 3,000 per sf. Using Advanced instead of Expensive Heavy Superior Streamlined materials adds $ 24,000 per sf.
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Old 11-04-2012, 01:57 AM   #23
Pomphis
 
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Default Re: [3e] F-111

I forgot: Radical Stealth is 4 lb per sf. Changing materials as above saves 3.375 lb per sf. So such a cost increase still means taking a small hit to performance.
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Old 11-04-2012, 03:21 AM   #24
gruundehn
 
Join Date: Oct 2005
Default Re: [3e] F-111

For aircraft there are two G-limits. The first is what we would normally think of, the maximum safe limit. But there is another and this other limit comes into play when the maximum safe limit is exceeded. This is normally around 11Gs but stating it that way can be misleading. If the maximum safe limit is 9Gs and you go to 10Gs then the original 11G excess limit becomes 10Gs, do it again and the excess limit becomes 9Gs, etc. If the excess limit ever hits 0Gs the airframe is no longer safe and is should be removed and scrapped or put on display.
I worked avionics in the USAF but this was covered in a maintenance briefinfor some reason I can no longer remember.
As far as the FB-111 (bad designation, it should have been BF-111) if I remember rightly it had completely different engines as did the EF-111. The FB-111 did not have the range to perform its mission and the B-52s were given priority for tankers so the FB-111s were considered by the aircrew to be suicide machines, at least in the 380th BW(M). I hated working on that bird.
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Old 11-04-2012, 07:15 AM   #25
Fred Brackin
 
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Default Re: [3e] F-111

Quote:
Originally Posted by Anaraxes View Post
The number you want to correlate to sustained maneuverability is probably "wing loading". .
But the number he wants to transklate to Vehicle aMR is the max safe G-load. That's how the stat is defined in Vehicles.
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Old 11-04-2012, 09:39 AM   #26
Doctor Thantos
 
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Default Re: [3e] F-111

I am curious as what you used to stat this.
Did you use Gurps Vehicle Builder for this aircraft? (or Gurps Vehicle Designer) or spreadsheet?

If you used one of the computer programs, do you have a file you would be willing to share?

Thanks,

DT.
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Old 11-04-2012, 01:57 PM   #27
cosmicfish
 
Join Date: Mar 2010
Default Re: [3e] F-111

As someone who has always been on the "yeah realism!" side of the GURPS debates, I just wanted to note that after a while the argument gets pointless, and this thread seems to have blown past that. There are usually many variations of aircraft depending on when it was made and upgraded, and all the fine details of how it performs and how that should be measured are useless if it goes beyond the resolution of the game.

Ultimately, the point should not be to precisely capture the F-111 in GURPS terminology. The point should be to get it close, and to make sure that it is reasonably balanced against everything else in the game.
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Old 11-04-2012, 05:41 PM   #28
Phaelen Bleux
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Default Re: [3e] F-111

Quote:
Originally Posted by Pomphis View Post
In RL, yes. In VE2 terms at TL7 Radical Stealth adds $ 3,000 per sf. Using Advanced instead of Expensive Heavy Superior Streamlined materials adds $ 24,000 per sf.
You also go from using metals to composites.

Quote:
Originally Posted by Doctor Thantos View Post
I am curious as what you used to stat this.
Did you use Gurps Vehicle Builder for this aircraft? (or Gurps Vehicle Designer) or spreadsheet?

If you used one of the computer programs, do you have a file you would be willing to share?

Thanks,

DT.
Long hand, really. A table of columns in a Word Doc. I really should do something better. But if you want it, I can PM it.

Quote:
Originally Posted by cosmicfish View Post
Ultimately, the point should not be to precisely capture the F-111 in GURPS terminology. The point should be to get it close, and to make sure that it is reasonably balanced against everything else in the game.
I would agree. . .designing real-world vehicles is a boat-load of juggling for fit. Sadly, I have never done much to check balance. I have designed most of the modern US jets, and a few Soviet and European models, but I have never compared them to each other to check how each one stats out compared to the next. Part of the problem is that there is no real GURPS refernce to start from, so all I could have is unofficial internal consistency. The second is that with all the fact checking to do the build, I'm a little burnt out on going back to make sure it looks good next to the last build. And as this thread proves, probably all my builds have some glitch I didn't notice.

Still, stuff like this helps me get as close as possible down the road, so I'm glad for it.
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Last edited by Phaelen Bleux; 11-04-2012 at 05:52 PM.
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Old 11-05-2012, 02:20 AM   #29
Pomphis
 
Join Date: Oct 2004
Default Re: [3e] F-111

I did a couple of modern designs too (pen and paper and pocket calculator). Most were for an IST campaign and include some non-RL components, typically a rE-cell instead of an auxiliary power generator. But it might still be interesting for a rough comparison.

Here is my F-4E:

McDonnell Douglas F-4E Phantom

TL 7 Fighter Size+5

Body: 850 cf / 539 sf
2 High-Agility Wings: 105 cf / 268 sf
Retractable Wheels: 42.5 cf / 74 sf
Totals: 1,102.5 cf / 1,149 sf, Drag: 111.5*, Lift Area: 589.9

2x Normal Crewstation with Ejection Seat/G-seat/HUD,
Mechanical Controls, Autopilot, 2x Precision Navigation Instruments, 2x LR-Com/Scrambler, Flightrecorder, GPS, IFF, Digital Vehicle Camera,
F: Radar 45 miles / Scan 21,
Adv Radar Detector, Adv Bombsight,
20mm Gatling from VE2, 640x SAPHE (WPS 0.4),
RoF 100, 3dx7 (0.5) + 1d-2 (2d), : 1,500, Max: 6,100, Acc 15,
18,650 lb Hardpoints (under body: 4x510 semi-recessed for AIM-7, 1x 4,610, under wings: 6x 2,000),
12 hours limited life support (2x 6 h), Compact Fire Suppression, rE-cell,
2x 12,000 lb thrust Turbojet, Afterburner,
2,000 gallons self-sealing standard tanks, Refuelling Probe,
Superior Streamlining, Sealed, DR 9 ExpMetal, HV Cheap Frame


EWt: 30,357.4 lb, Fuel: 13,000 lb, Hardpoint payload: 18,650 lb, LWt: 62,500 lb
Cargo/empty: 35.248 cf
Cost: 2,462,343.4 $

Clean Configuration: aSpeed/Afterburner: 1,555 mph (Mach 2.04), aSpeed: 1,270 mph (Mach 1.67),
cruiseSpeed: 735 mph (Mach 0.96)
With 10 loaded Hardpoints: aSpeed/Afterburner: 1,345 mph (Mach 1.76), aSpeed: 1,095 mph (Mach 1.44),
cruiseSpeed: 635 mph (Mach 0.83)
Endurance with Internal Fuel: 37 minutes at aSpeed, 1 hour 51 min at cruiseSpeed

aMR: 6
aAccel (Afterburner): 11 mph/s

StallSpeed: 165 mph
gAccel (Afterburner): 15 mph/s, gAccel: 12 mph/s, gDecel: 10 mph/s
Takeoff Runway (Afterburner): 454 yards, Takeoff Runway: 568 yards, Landing Runway: 681 yards

HT 10 / 1,617

Special Effect: semi-recessed hardpoints increase Drag by 1 if empty, only 2 if occupied


Note that aMR is calculated for maximum weight, in an air-to-air role weight would be less, and aMR more.
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Old 11-05-2012, 08:49 AM   #30
Phaelen Bleux
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Default Re: [3e] F-111

Here's my F-4:

http://forums.sjgames.com/showthread.php?t=70143
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