eagleSidewinders can be carried in place of the HARMs if necessary. That would be stations 2 and 10 from post #2.
eagleSorry, I have serious doubts on the 8.5 G claim. As External Fuel Tanks have a big impact on drag. Which, clearly has an even larger impact on “Instantaneous Turn Rates” and “Sustained Turn Rates”. So, its very hard for me to believe. Carrying External Fuel Tanks has very little or no impact on G’s. To concede I would need much more than one comment from a poster @ f-16.net…………(though I highly respect most members)
Drag doesn’t really matter in this case.
Further, while the semi-recessed AMRAAM’s have less drag. They still pay a penalty if small. Yet, the outboard Pylons, Missiles, and External Fuel Tanks pay a high price……..:(
In drag, yes.
Remember, the “Drag” and “Weight” of External Fuel Tanks is so great. That it consumes half the fuel just to carry them…………….So, unless you have some magical evidence that Typhoon External Fuel Tanks are some how drastically more efficient than other tanks from all around the world. I see no advantage compared to 5th Generation Types.
Weight of empty fuel tank is less than for an AAM. Most fighters are designed to fight with 6-8 missiles so the weight of 2 tanks doesn’t matter.
With full tanks, you don’t enter a fight.
That said, I will admit the Typhoons arrangement of 4 Semi-Recessed Air-to-Air Missiles has less impact than most of its contemporaries on drag………Yet, when you start to add external pylons, missiles, and external fuel tanks. That changes everything……..
In short the drag associated with External Weapons and Fuel is less than many of its 4.5 Generation Competitors. Yet, it is hardly of no consequence…….
Respectfully,
Scooter
True, the EF has a pretty good AAM arrangement and adding stores has a negative impact as always. But with such a light load, 9Gs are no problem.
Btw: the original F-15 missile load is ~1300kg. (4 Sparrows + 4 Sidewinders)
4 ASRAAMs + 4 AMRAAMs are ~ 1050kg. Add the tanks and they’re about equal.
eagleIndeed all true, but none of those planes have nearly the same performance loaded with gas bags and missiles as they do when flying clean and that it the whole point of this thread. A combat loaded Typhoon, F-15, or (fill in your favorite fighter that normally carries stores externally here) will not have the same performance as a clean Block 50 Viper. Conversely a combat loaded block 50 viper will not have the same performance as a clean Typhoon, ergo if the F-35 has the performance of a clean viper while combat loaded then it would seem to me and I would guess any other rational person that it would do just fine in A2A even without stealth.
Of course a combat loaded jet will not have the same performance as a clean jet. But some characteristics like the ability to pull 9Gs remain when loaded with some AAMs and empty tanks. Others like acceleration and top speed suffer.
The point is, the EF can maneuver unrestricted carrying such a load leading to minimal performance drawbacks in a turning fight. I guess the pilot’s statement is a little bit exaggerated or misinterpreted.
eagleSorry, even empty no aircraft can pull 9 G’s with external fuel tanks………:eek:
AFAIK, F-16 is unrestricted with a centerline fuel tank and F-15 probably too.
Those tanks weigh less than the A/A missiles carried further out from the centerline so the missiles have greater impact. It depends on fuel tank limitations etc. so older tanks have limits. F-16 370gal underwing tanks f.e. are limited to 8.5Gs (http://www.f-16.net/f-16_forum_viewtopic-t-1666.html)
EF tanks are new design and if the pilot says they’re unrestricted, why not.
Also, 6 AAMs on an EF are considered clean. That’s the 4 semi recessed -120s and the outboard SRAMs whose pylons are carried always as they contain the chaff launchers.
2 additional missiles plus empty tanks plus pylons is not such a big deal then.
eagleBTW No fighter can make a “9G” turn with external fuel tanks……..
Of course it can.
Depending on filling level obviously. 😉
Edit: and no, tanks are probably not full when arriving at training ranges. So 9Gs.
eagleThe trouble with pfcem is that he can’t tell the difference between stalled and non-stalled flight. It’s appalling for a person that actively participate a forum such as this one…and I’m not sure whether the rest of his posts regarding prices and such has any meaning, or are pure gibberish?!
Cheers, Cola
AFAIK, the F-22 experiences slight buffeting when braking the soundbarrier. Doesn’t mean its stalled does it.
eagleYou do not even try to understand the basics.
In the most simplified way, when we do leave aside the amount of thrust generated by the propulsion-system (inlet-outlet) and the speed, the
installed thrust does drop with the height (air-pressure), but the dry and the afterburner thrust are not affected in the same way.
When dry is down to 25% at ~40.000 feet, the wet is 50 % only.
To have the same installed thrust like the F119 in dry at that height, the F100 is in need of stage 1 or part of the AB only. 😉
I try to understand.
But thrust is not really the problem. Fact is both have roughly the same top speed fully armed, the F-22 in supercruise and the F-15 with AB. Top speed implies full AB not stage 1. Full AB implies max. fuel flow.
If you say dry is at 25% and AB at 50% at 40k feet, the F-22 has doubled its advantage. Inlet-outlet aside.
eagleIt does show, that you have not the slightest idea, what you are talking about to stay polite.
What is the generated thrust for both at 40.000 feet and Mach 0,8 to start with?
I don’t know. Do you know?
That’s why I used the numbers known.
For some help I did stick to subsonic at first, because the installed thrust does give ~82% of the total from the propulsion system.
To keep things much more simple. Ask a friend to “fly” the Learjet in the MS Flightsim X and watch the fuel-flow at IAS of 250 kt at different heights or keep the same power-setting of 90%. Maybe you notice I do not speak about thrust, but you will get a graph from that.
Just the first stepping stone to start with.
Obviously fuel flow decreases. As we do not have exact data, lets assume it decreases at the same rate for both. The result stays the same, i.e. around 3 times the supersonic endurance.
edit: if dry thrust and thus fuel flow decreases faster, the gap only grows…
eagleIt is not and the designer of the F-22 did not invent the physics new.
To reach the required mission radius the supersonic time is limited or it will suffer. But you can give us a typical mission with the related data to bolster your guess. 😉
Just some rough numbers:
F-15C wet thrust: 2x 24,000lbs
Fuel consumption: 96,000lbs per hour (SFC ~2lbs/h/lb thrust) or around 8,4min using the 13,500lbs of internal fuel.
F-22A dry thrust: 2x 27,000lbs
Fuel consumption: 43,200lbs per hour (SFC ~0.8lbs/h/lb thrust) or around 25min using the 18,000lbs of internal fuel.
Both flying at ~M1.8 fully armed.
eagleIt is not and the designer of the F-22 did not invent the physics new.
To reach the required mission radius the supersonic time is limited or it will suffer. But you can give us a typical mission with the related data to bolster your guess. 😉
The supersonic time is limited obviously as the F-22 still uses lots of gas. But it uses less than other fighters with afterburners. If not, supercruise would be useless.
The price is higher fuel consumption at subsonic speed.
There was a nice F-22/F-15 comparison somewhere that showed the F-22 uses x times less fuel at supersonic speed. Can’t find it right now.
eagleIt is easier/more efficient to accelerate a large mass to a low velocity then a small mass to high velocity with equal ZxY so that’s the preferred way.
That’s what the F-22 does when supercruising in dry thrust as opposed to using afterburner in something like an F-15.
It may need more thrust (its heavier afterall) but fuel consumption is lower.
eagleSorry but that is just plain wrong. You guys only talk about thrust and think that this solves it all. It doesn’t. If you attach a 300kN engine on a barn door, it won’t fly Mach 3.0. Aerodynamics is the key. Raptor has fixed intakes for a good reason (stealth, weight savings) but that also comes at a price. Refer to MiG-23M vs MiG-27 comparison, where the latter equipped with fixed intakes, despite of having a much stronger engine, barely exceeds M1.6 while the 23M easily hops over M2.2.
Intakes can be “fixed” (i.e. designed) with supersonic performance in mind. On the Tornado f.e., they could have locked the intakes at M2.35 settings. So fixed intakes don’t exclude high speed. See the F8U-3 about that.
F-22 intakes are optimised for M1.5 I think.
eagleGripen NG has a ferry range of 2500 km w. internal fuel only; 4075 km with drop tanks; that’s 63% increase in range. AFAIK, it is not common practice to drop the tanks when you are out “ferrying”. Also it is quite common for 3. gen and 4. gen fighter jets to use drop tanks when training. If a 30% increase in fuel adds just an 8% increase in range, do you really think they would regularly use drop tanks when training?
That’s 1500km more ferry range with 3 tanks I suppose, or 500km per tank or half the combat range increase for 1 tank. That ferry/combat difference looks about right.
I agree about the 30% fuel increase/8% range increase. With those numbers, external tanks could be dropped. 😮
eagleCan Hornets with buddy/buddy packs achieve the same level of AAR provision? Imagine multiple bolters need refuelling in quick time?
I don’t know, but there are more tankers available in theory (up to 24) and if the situation requires more tankers in the air, some F-18E/Fs could be launched quickly I suppose.
The F-18E/F is not the most efficient tanker obviously, but thanks to its 4 480gal external tanks, it can probably offload more than the S-3, which is more efficient but carries much less fuel.
eagleF-22 published (by the air force) max speed is M2 plus, but who really cares when you can supercruise at close to M2. That is the relevant tops speed.
Agreed.
More F-35 engine info for those who want to learn. Again, trolls need not reply.
http://www.f135engine.com/proven-tech/engine_chacter.shtmlI am not sure how much real difference there is between the production 43K and the de-rated 41K for the early test aircraft engines.
Since the F135 is based on the F119 which has 35,000-39,000 (or more?) pounds of thrust, I bet the F135 with increased bypass has significantly more than 39k. Even 43k seems low. Static of course.
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