Operational Performace Comparison: Viper, Beagle, and Stubby

The F-35 compared with other modern jets.
  • Author
  • Message
Offline

marsavian

Forum Veteran

Forum Veteran

  • Posts: 622
  • Joined: 02 Feb 2018, 21:55

Unread post05 Oct 2018, 14:58

gta4 wrote:And I seriously doubt whether Typhoon has energy advantage compared to a F-15E-229/129 (no CFT).


I doubt it too, that F-15E intercept spec has the best full internal fuel/AAMs thrust/weight ratio of anything, 1.2+.
Offline

aasm

Banned

  • Posts: 77
  • Joined: 12 Aug 2018, 13:01
  • Warnings: 2

Unread post06 Oct 2018, 15:32

marsavian wrote:
gta4 wrote:And I seriously doubt whether Typhoon has energy advantage compared to a F-15E-229/129 (no CFT).


I doubt it too, that F-15E intercept spec has the best full internal fuel/AAMs thrust/weight ratio of anything, 1.2+.


Typhoon empty weight, 11T
full internal fuel 4T

roughly same ballpark.
Offline

marsavian

Forum Veteran

Forum Veteran

  • Posts: 622
  • Joined: 02 Feb 2018, 21:55

Unread post06 Oct 2018, 16:02

5t not 4t.

Thrust of Typhoon = 40,500 lb
Weight with internal fuel = 35,000 lb

T/W ratio = 1.16

Thrust of F-15E with -229 = 58,300lb
Weight with internal fuel (No CFT) = 45,200lb

T/W ratio = 1.29

Not quite the same ballpark.
Offline

chucky2

Active Member

Active Member

  • Posts: 110
  • Joined: 08 Jul 2016, 20:27

Unread post31 Oct 2018, 02:09

sprstdlyscottsmn- Just curious on why the F-15E is so much heavier than the -D? Did they really need 20k weight increase to strengthen the frame/wings for the A-G role?

If so, one wonders what a F-15E (or the newer F-15SA/QA) could be like with modern design/manufacturing...
Offline

sprstdlyscottsmn

Elite 3K

Elite 3K

  • Posts: 3714
  • Joined: 10 Mar 2006, 01:24
  • Location: Phoenix, Az

Unread post31 Oct 2018, 05:19

In terms of empty weight the E clocks in at 35,030lb without the CFTs. An early 2000's F-15D tips the scales at a mere 30,000lb. This is with Aircrew at 215 each per the -1. That 5,000lb is all the strengthening and wiring for the A-G work. Remember the F-15E is still a basically 9G aircraft at any weight unless transonic at altitude. The stores G limits are the limiting factors.

The bulk of the added weight is the CFTs at 4,386lb empty or 13,738lb full. In addition to that is the 1,141 of targeting pods that the F-15E carries even on counter air missions.

That is why for any given loadout the E is 20,000lb heavier than the D.

If we are talking an Israeli D model (the only Ds I can think of that would use CFTs) then the difference is much smaller. D CFTs weigh 2,487lb empty and 12,001full.
"Spurts"

-Pilot
-Aerospace Engineer
-Army Medic
-FMS Systems Engineer
Offline

zero-one

Elite 1K

Elite 1K

  • Posts: 1767
  • Joined: 23 Jul 2013, 16:19
  • Location: New Jersey

Unread post31 Oct 2018, 09:28

Would an air to air configured E model perform better than it's C counter part?
Reason I ask is because I'm not sure if the extra support structures on the E would somehow affect the aircraft's stability in some way. And according to sprstdlyscottsmn, stability can be every bit as important as Lift loading and wing loading.
Offline

sprstdlyscottsmn

Elite 3K

Elite 3K

  • Posts: 3714
  • Joined: 10 Mar 2006, 01:24
  • Location: Phoenix, Az

Unread post31 Oct 2018, 13:51

You may want to clarify. When Es have been tasked for anti air they still carry the CFTs, targeting pods, and wing drop tanks. They are heavy beyond reason. CFTs do cause stability to relax in pitch but also increase the moment of inertia in roll.

If you are asking about a theoretical E that is configured like a D but with the PW-229 motors then the added thrust will offset the added weight and allow for quick accelerations but the other agility metrics will still suffer.
"Spurts"

-Pilot
-Aerospace Engineer
-Army Medic
-FMS Systems Engineer
Offline

zero-one

Elite 1K

Elite 1K

  • Posts: 1767
  • Joined: 23 Jul 2013, 16:19
  • Location: New Jersey

Unread post31 Oct 2018, 16:53

When Es have been tasked for anti air they still carry the CFTs, targeting pods, and wing drop tanks


Don't C's also carry all of those, except for CFTs?
Anyway, if I'm reading this right, an E model configured for A-A (with CFTs, pods and EFTs) will still be inferior to an A-A configured C (with EFTs, and targeting pods) even with the added power from the 229s
Offline

sprstdlyscottsmn

Elite 3K

Elite 3K

  • Posts: 3714
  • Joined: 10 Mar 2006, 01:24
  • Location: Phoenix, Az

Unread post31 Oct 2018, 18:24

Correct. It will still be 20,000lb heavier than a Charlie when both have the same items strapped to the wings.
"Spurts"

-Pilot
-Aerospace Engineer
-Army Medic
-FMS Systems Engineer
Offline

chucky2

Active Member

Active Member

  • Posts: 110
  • Joined: 08 Jul 2016, 20:27

Unread post31 Oct 2018, 20:26

Thanks Spurts, was just curious.

If they used the same CFT on the E as is used on the D though, they'd basically by 'only' 5K different, then the option of having the pods on there would have to be decided.

I wonder if with ADCP II, which has much more processing power than the old computer, if the pods could somehow be integrated into the E or at least reduced in weight/size. Just seems like there ought to be opportunities for lots better integration given the large leaps in processing power from the 80's until now.
Offline

zero-one

Elite 1K

Elite 1K

  • Posts: 1767
  • Joined: 23 Jul 2013, 16:19
  • Location: New Jersey

Unread post01 Nov 2018, 07:40

Thanks sprstdlyscottsmn, we could always count on you for these calculations.

Curious though, what would be your best performing Eagle for A-A? Export models included. Remember the SA and QA variants had integrated IRSTs so theres no drag penalty from pods (not sure how much drag the integrated IRST will have) They also have GE-129 motors. but I noticed they're also heavy as heck. 37,000 lbs empty...

Wish they would do an engine upgrade program for the C2040 program, Charlie with 229 motors. Look out Flankers. :mrgreen: :mrgreen: :mrgreen: :mrgreen:
Offline

gta4

Forum Veteran

Forum Veteran

  • Posts: 751
  • Joined: 17 Oct 2010, 19:10

Unread post01 Nov 2018, 14:02

The precised measured weight of F-15E with GE129 is 33843 lbs.
F15E GE129 empty weight.jpg


This should be the best air 2 air configured Eagle.
Offline

mixelflick

Elite 2K

Elite 2K

  • Posts: 2574
  • Joined: 20 Mar 2010, 10:26
  • Location: Parts Unknown
  • Warnings: 1

Unread post01 Nov 2018, 15:20

zero-one wrote:Thanks sprstdlyscottsmn, we could always count on you for these calculations.

Curious though, what would be your best performing Eagle for A-A? Export models included. Remember the SA and QA variants had integrated IRSTs so theres no drag penalty from pods (not sure how much drag the integrated IRST will have) They also have GE-129 motors. but I noticed they're also heavy as heck. 37,000 lbs empty...

Wish they would do an engine upgrade program for the C2040 program, Charlie with 229 motors. Look out Flankers. :mrgreen: :mrgreen: :mrgreen: :mrgreen:


You know, I've always wondered why USAF Eagles flew with "just" the F-100 rated at 23,000lbs thrust (or thereabouts), vs. the 229 or the more powerful GE engines. I vaguely recall at an airshow one F-15C pilot telling me, "they tried more powerful engines" in the C, but something about it didn't fly (figuratively, not literally LOL).

Why wouldn't the USAF want its long standing air superiority platform to have more powerful engines? They're out there so... is it just $???
Offline

sprstdlyscottsmn

Elite 3K

Elite 3K

  • Posts: 3714
  • Joined: 10 Mar 2006, 01:24
  • Location: Phoenix, Az

Unread post01 Nov 2018, 15:38

Well gta, that was the weight of that eagle at that time. We don't know if that included oil and unusable fuel either. For reference, the F-15E-1 printed in 1993 states the weight of an F-15E with -229 motors is 34,600lb with a note "For precise airplane basic weight, refer to weight and balance data handbook for the particular airplane." Also, this lists that the -229 motors "increase the aircraft weight by 1,200lbs and shift the cg aft approximately 0.8%" Just more food for thought.

Zero-one, I ran some numbers once for a GE-129 powered Charlie. It would have been an absolute beast. No such aircraft exists however. Be careful will your statement of integrated IRST. It is the integration of the air-to-air IRST21 into the PYLON of the ATFLIR pod. When it comes to straight line stuff the SA operating as a heavy D will be the best performer. When it comes to turning performance I would give that to the old A model. Weight is the enemy of turns for any given wing.
"Spurts"

-Pilot
-Aerospace Engineer
-Army Medic
-FMS Systems Engineer
Offline
User avatar

sferrin

Elite 3K

Elite 3K

  • Posts: 4810
  • Joined: 22 Jul 2005, 03:23

Unread post01 Nov 2018, 19:55

sprstdlyscottsmn wrote:Zero-one, I ran some numbers once for a GE-129 powered Charlie. It would have been an absolute beast.


Did you use the 36,500lb thrust version? :shock:
"There I was. . ."
PreviousNext

Return to F-35 versus XYZ

Who is online

Users browsing this forum: No registered users and 6 guests