F-14 low speed prowess vs Other Aircraft

[GGTharos]

Did you use payload that was something other than 'clean'?

[captain_dalan]

Yeah, 2XAIM-54, 2XAIM-7, 2XAIM-9 and i was burning right through the 8000lbs of fuel while doing it, so it was bellow 50% internal fuel. I would like to make more precise tests, but the fuel burns up so fast in zone 5, the total weight changes by seconds and not by minutes :(

[GGTharos]

Yeah you should be seeing something like 2500lbs/min consumption I think.

 

Probably a 40000lbs eagle is more comparable then, with all kinds of things hanging off of it :)

[Hummingbird]

Nah, the F-15 would probably do around 9 in similar conditions.

 

Not according to the charts ^^

 

With the same amount of fuel as the F-14 it would probably do 8.5 G at Mach 1, but I'm not so sure it would do 8.5+ G.

[captain_dalan]

Not according to the charts ^^

 

With the same amount of fuel as the F-14 it would probably do 8.5 G at Mach 1, but I'm not so sure it would do 8.5+ G.

At half a fuel though, it goes above 9 with 4+4 AAMs. At least the 220's do.

[Hummingbird]

At half a fuel though, it goes above 9 with 4+4 AAMs. At least the 220's do.

 

That might be, but wouldn't it be more fair to compare them at the same fuel loads? :)

[GGTharos]

Why is it more fair to have same fuel loads instead of percentage of fuel?

 

How about comparing based on fuel remaining for combat? :)

[Hummingbird]

Why is it more fair to have same fuel loads instead of percentage of fuel?

 

How about comparing based on fuel remaining for combat? :)

 

The reason I'm thinking it might be more fair with similar fuel load is that it would translate into time available to fight :)

[GGTharos]

Different engines have different fuel consumption specs, so this is not necessarily the case.

One of the huge advantages the 110 brought to the F-14 is higher thrust at military power or less, allowing it to cruise at higher altitudes without trouble. This had an enormous effect on fuel economy (fuel consumption is reduced at altitude for the same throttle setting. Of course, so is thrust).

 

But light the cans, and you're going to see fuel consumption that will instantly turn you into a tree-hugger :)

[lunaticfringe]

Trees-shmeez.

 

Drill Baby, Drill.

[Hummingbird]

Different engines have different fuel consumption specs, so this is not necessarily the case.

One of the huge advantages the 110 brought to the F-14 is higher thrust at military power or less, allowing it to cruise at higher altitudes without trouble. This had an enormous effect on fuel economy (fuel consumption is reduced at altitude for the same throttle setting. Of course, so is thrust).

 

But light the cans, and you're going to see fuel consumption that will instantly turn you into a tree-hugger :)

 

Well yes ofcourse, but I'm assuming that since they use the same engine they're not that different from each other in this regard :)

[Exorcet]

The reason I'm thinking it might be more fair with similar fuel load is that it would translate into time available to fight :)

A lighter plane needs less fuel to perform the same maneuvers though (all else even). Going by load is going to handicap the F-15. I think the only comparison where load makes sense rather than fraction is weapons load because the weapons have a fixed weight and both aircraft carry essentially the same loadout (not counting AIM-54 of course).

[Hummingbird]

A lighter plane needs less fuel to perform the same maneuvers though (all else even). Going by load is going to handicap the F-15. I think the only comparison where load makes sense rather than fraction is weapons load because the weapons have a fixed weight and both aircraft carry essentially the same loadout (not counting AIM-54 of course).

 

Hmm... I guess that depends on the drag that the engines have to overcome. But without knowing the actual fuel consumption we're just guessing.

 

Seems natural to compare the two with as similar a loadout and fuel weight as possible though IMHO.

[captain_dalan]

Hmm... I guess that depends on the drag that the engines have to overcome. But without knowing the actual fuel consumption we're just guessing.

 

Seems natural to compare the two with as similar a loadout and fuel weight as possible though IMHO.

But that just would not make sense for planes with smaller tanks. There are planes out there that can't even takeoff with a load that a Flanker or a Tomcat would consider "combat load"...

[Hummingbird]

But that just would not make sense for planes with smaller tanks. There are planes out there that can't even takeoff with a load that a Flanker or a Tomcat would consider "combat load"...

 

Considering that we're comparing two aircraft both sporting two similar engines, it is as simple as giving both aircraft the same fuel load if you ask me.

 

So if we want to avoid exterior tanks, well then we just set the bar at the max internal capacity of the F-15 and bingo we got a fair match up (providing a similar armament ofcourse).

Edited March 25, 2015 by Hummingbird

[Exorcet]

Hmm... I guess that depends on the drag that the engines have to overcome. But without knowing the actual fuel consumption we're just guessing.

 

Seems natural to compare the two with as similar a loadout and fuel weight as possible though IMHO.

With induced drag, weight impacts drag. This is one of the reasons why you look at fuel fraction. Fuel is energy to perform work (fight drag). Also consider vertical maneuvers, to push the plane up to a new altitude, you need to do work. The amount of energy needed to be expended depends on the weight.

 

Estimating fuel burn in combat might be a bit complex, but we estimate fuel needed to get to and from a combat zone using the range equation (which can be turned into a time equation by dividing by velocity):

 

R = V(L/D)/TSFC*ln(mi/mf)

 

Assuming the same V, L/D, and TSFC, the same fuel fraction will give the same range no matter the actual weights involved. This implies that giving a smaller plane the same load as a larger one is pointless. The caveat though is that the planes probably don't have the same cruise speed (and transonic effects aren't captured here) and L/D. With swing wings the F-14 probably has an L/D advantage which would allow it to cruise on less fuel than its weight would suggest.

[captain_dalan]

With swing wings the F-14 probably has an L/D advantage which would allow it to cruise on less fuel than its weight would suggest.

And if i recall correct from the old USNF days, at a somewhat lower cruise speed.

 

 

So if we want to avoid exterior tanks, well then we just set the bar at the max internal capacity of the F-15 and bingo we got a fair match up (providing a similar armament ofcourse).

No such thing as a fair fight. Most configurations in the flight manuals are given that way for a reason. They are considered relevant. And for most AS missions it means (most of the time), that the plane is expected to fight at 50% internal fuel (60% for navy birds, i suspect because of the safety margin of carrier landings). But you are on the CAP, and a fight comes to you without asking, you are going into it with what you have, or bug out.

[turkeydriver]

And if i recall correct from the old USNF days, at a somewhat lower cruise speed.

 

 

No such thing as a fair fight. Most configurations in the flight manuals are given that way for a reason. They are considered relevant. And for most AS missions it means (most of the time), that the plane is expected to fight at 50% internal fuel (60% for navy birds, i suspect because of the safety margin of carrier landings). But you are on the CAP, and a fight comes to you without asking, you are going into it with what you have, or bug out.

 

We've effectively "Nuked" this. The F-15 and F-14 aren't designed to enter fights at the same specific weights regarding fuel or even percentages.....What I mean is, an F-14 will take off with full gas and get little sips ideally from a Navy tanker and then ideally fight out at the edge of its CAP around 50%(or less!) If the threat is known once they tank, they're going to establish an intercept at a higher rate of speed and enter the merge at low gas as well.

 

Ideally an F-15 flight is supported by a KC-135 or KC-10 that keeps it as close to full as possible. It cruise and patrol on the gas in its wing tanks and will most likely start a furball with a higher internal fuel percentage, as they'll burn the externals down and punch them off unless max speed is needed NOW. With the Eastern Iraq intercepts running down aircraft trying to escape being negated (all high speed chase downs that burned a LOT of gas), I think we can safely say the majority of F-15 fights happen with higher fuel loads than an F-14 and may very well have consumed more.

 

Regarding staying power in the fight, the F-14 should win the wings programmed at auto, the TF-30 is a very fuel efficient engine at lower altitudes, with the F-110 burning more gas during cruise, but not needing the afterburner usage as much during climb out. If you want to compare the aircraft, you need to make 3 comparisons.

Understand that in ACM, the F-14A will set the TF-30s in Zone 5 and leave them there, so it will have 40k of thrust throughout. The F-14B and F-15 will adjust throttle settings as needed to stay behind their bogey.

In my mind, knowing this about the F-14A, it would make the fight against it easier, because you know the pilot can't play with throttles, and will use the vertical plane to control your energy state, so you know where he's going to go. The F-14B and F-15C can choose their maneuvering plane at will, so they would be much tougher to anticipate. That's where the real discussion lies, as pilots don't just fly to airplane strengths, the F-14A driver has a smaller bag of tricks, and the smarter enemy could use that to win more possibly, this may be why some Air Force jocks think the F-14 is easy to beat in a knife fight, because they can guess where most of them( F-14As) are going to go.

[captain_dalan]

I don't really know what to make out of all this without a clear cold war doctrine read at hand. I can only give MY opinion on it, but i doubt it will be worth much (from a strategic point of view anyway).

 

However, considering the engines and fuel consumption, even though the GE's consume more fuel per unit of time then the PW's, they also produce more thrust, thus you can effectively spend more time at cruise speed, while at lower throttle setting, which increases your CAP time even more.

 

P.S. If anyone has a good (non-classified) document on navy doctrine, intercept procedures, rules of engagement i would certainly appreciate the good read :thumbup:

 

EDIT: i don't think the need to plug the burner effectively limits the F-14A to the vertical fight, especially not at lower altitudes where you can still get some use of full military power without risking a flame out when you switch to AB, but the throttle restrictions can be a restrictive element, yes.

Edited March 26, 2015 by captain_dalan

[lunaticfringe]

Section III-I, pages 651 and following. You're not going to get a later generation's material for at least another five years or so on the Navy side: I've already tried. As to the perception for how the USAF is going to run their CAPs, let's just say history hasn't shown that to be the case.

 

And with regards to what the F-14A is going to do, in dealing with both pilots and maintainers, the 414s were appreciably more resilient to throttle change. Not perfect, but you were able to negotiate transitions if smooth- the more time you took handling the throttle, the better.

[captain_dalan]

You are referring to the flight manual?

[lunaticfringe]

No, the other one. About the jet that's not the F-14.

[captain_dalan]

Roget that! :thumbup:

[captain_dalan]

That was some long reading (and not yet finished if i might add). Still, from everything i've read so far, the doctrine for intercepts and CAP/DLI's varies by quite a margin depending on the mission at hand and external conditions. And although a possibility exists for which flights could be ordered to sacrifice CAP flexibility by going to a high speed/low fuel intercept, it is strongly advised for great caution before such a measure is taken.

 

Furthermore, page 670, under chapter Factors Affecting Deployment of CAP/DLI clearly states:

"The cycle time of a CAP or DLI, should provide enough fuel to conduct the flight, complete one or more intercepts and have sufficient fuel remaining to delay recovery until the raid has departed the vital area. In order to accomplish this, the cycle time should be based on a maximum landing weight, plus an expendable fuel package of several thousand pounds."

 

This and another simulated exercise schedule that involves no immediate tanking support, leads me to believe that though refuel at station is a viable option in at least some situations, more often then not, CAP is being setup in such a way that the section/flight can perform it without mandatory refueling. Especially during critical times.

 

Besides, wouldn't it be extremely irresponsible to let the jets duke it out on fumes?:huh:

[turkeydriver]

I don't really know what to make out of all this without a clear cold war doctrine read at hand. I can only give MY opinion on it, but i doubt it will be worth much (from a strategic point of view anyway).

 

However, considering the engines and fuel consumption, even though the GE's consume more fuel per unit of time then the PW's, they also produce more thrust, thus you can effectively spend more time at cruise speed, while at lower throttle setting, which increases your CAP time even more.

 

P.S. If anyone has a good (non-classified) document on navy doctrine, intercept procedures, rules of engagement i would certainly appreciate the good read :thumbup:

 

EDIT: i don't think the need to plug the burner effectively limits the F-14A to the vertical fight, especially not at lower altitudes where you can still get some use of full military power without risking a flame out when you switch to AB, but the throttle restrictions can be a restrictive element, yes.

 

Just trying to point out that those TF-30s worked well and the F-15 pilot knew that when the F-14 had energy, they would use the vertical to prevent an overshoot, or to bleed energy when needed. Conversely, F-14 jocks call F-15s easy kills because their action after the merge was the same thing for every pilot on the first fight.