U guys are doing the mistake again to srgue with MiG_23M.
That can be as bad as starting am argument with alvis.
Leads absolutly nowhere because those guys are so convinced of their own opinion and can never be wrong
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I don’t know what you’re getting at here.
That bit on Harrier will have been with reference to the F-35 most likely, since that was the projected replacement. The paper you provided talking about the SHAR replacement is not relevant because a) SHAR isn’t the Typhoon, b) the Pegasus and c) if you’d actually assimilated what the whole of that one page read, they basically stated it would have to be a STOVL Carrier due to the projections on what the Invincible replacements would be (practically guaranteeing it would need to have a VTOL capability) - which diminishes the relevance sizeably because by this point the EFT was a fairly “in progress” project: the prototype had already been flown and the engines ground tested heavily (and installed to my knowledge) by the point of that evidence being formulated. Hence my confusion as to why you’re interested in the SHAR paper which appears to be not in the slightest relevant.
Your second bit of “evidence” reads more like a “that’s what they sometimes do” and there are many sources that have been presented in this thread that support the idea that no afterburner is required for supercruise.
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Dude’s name is mig-23, can you see why you shouldn’t argue with him?
Lol what a piss take
This is like saying that the Su-35 cannot go supersonic without afterburner because of the engine on the Yak-38
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Dunning-Kruger Effect in full view. I’m certain psychologists would have a field day on these forums, if mental gymnastics were a sport, we’d have some record breakers right here.
Mate, just because the Russians can’t build a decent jet engine doesn’t mean the West can’t either lmao
That certainly can’t be the case, as the 6th Gen studies didn’t begin until the 2010’s, 20 years after this claim. Meanwhile, the F-35 was still undergoing development, so it’s definitely in reference to that
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I assume you are choosing the RM12 and M88 as examples of engines which can super cruise (both the Rafale and Gripen are widely cited as super cruise capable)? The Ej200 compares favourable to both of those in terms of mass flow rate and specific thrust (thrust produced per unit of flow rate). Also of note is that it uses a convergent divergent nozzle, which by now means unique does give it a supersonic performance advantage over the M88, which only has a convergent nozzle.
| Engine | Mil Thrust (lb) | Max Thrust (lb) | Mass Flow (lb/s) | Mil Specific Thrust (lbf/lb/sec) | Max Specific Thrust (lbf/lb/sec) |
|---|---|---|---|---|---|
| EJ200 | 13,500 | 20,200 | 168 | 80.36 | 120.24 |
| M88 | 11,200 | 16,900 | 143 | 78.32 | 118.18 |
| RM12 | 12,100 | 18,100 | 152 | 79.61 | 119.08 |
The F119 is undoubtedly a very impressive engine, but I’m not sure how it (or the rest of this comment is relevant to the EJ200’s ability to super cruise or not).
I’m not aware of the EJ200 having a variable bypass ratio. I believe it is fixed at 0.4.
As you say that paragraph is talking about a replacement for the Sea Harrier. That aircraft was to be a STOVL aircraft and I doubt the EJ200 lent itself particularly well to conversion into a STOVL / VTOL engine. I must admit I’m not too familiar with that period but I know at the time the UK was working with the US on various STOVL projects (SSF, ASTOVL, JAST - which became JSF) so the comment was likely being made with regard to one of those.
Thanks I’ll try and find time to give that a proper read.
An archived version of the Eurofighter website says it can accelerate to supersonic speeds on dry power. So as you say that’s probably talking about using afterburner to get to high speeds quicker, rather than it being necessary to get to high speeds.
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At this point i dont know if you are talking about the link, or the thing it leads to
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Looking at the link is like looking hieroglyphics
When i try to open it it says Ur session timed out
Am I reading this correctly that this Mig 23 guy argues that the EF cannot supercruise, despite all available (serious) documentation stating otherwise? What is wrong with this man
Huh that’s weird idk why it’s doing that
Made a screenshoot
Spoiler
yes thx
Fortunately or unfortunately we have to give everyone some leeway to be daft. seeing as we all do it from time to time.
Just, it defies logic. Harrier’s replacement was always likely going to be what the JSF program turned out, simply because Typhoon was never going to be Carrier Capable in any meaningful manner that would be useful to the UK (MiG-23’s SHAR paper identifies any successor to the Invincibles as likely to be a small, STOVL carrier)
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Your link but in short
Or make
[Insert here] (link here) without the space between each other
The Insert part will be the short name for the link
Supercruise ability is largely determined by airframe drag and engine exhaust velocity (Specific Impulse).
NOT engine thrust.
The royals Royce spey engines produce a similar thrust as the EJ200, but the FGR/FG1 phantoms do not have any kind of supercruise ability.
Even the F414-GE-400 on the super hornet has far superior thrust and a bypass ratio of 0.25:1 but it has no ability to supercruise whatsoever.
The above aircraft have too much drag and not enough specific impulse on military power to be able to achieve supercruise.
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That is not sound logic.
I don’t see “most sources”, only Austrias defunct webpage that also seems to have been from a time when it was assumed the Eurofighter could match the public F-22 Super cruise data and overestimates the thrust to weight ratio of the EJ200 to be 10:1.
The following claim of acceleration from subsonic to supersonic without reheat is not properly linked to a source
The fuel burn specifications are far inferior to the F-22, aiding my point in the discussion. That’s also not quite correct as 0.74 was the goal and 0.81 lb/lb-f hr was the lowest achieved with mil thrust cruise. As the temp limits increase to allow for higher speed and possible super cruise they actually end up decreasing efficiency as they pass beyond the efficiency envelope.
By comparison the F-22 is estimated closer to ~0.65 lb/lb-f hr subsonic and on less than mil thrust while full mil thrust provides closer to 0.8 lb/lb-f hr but at a sustained super cruise speed in excess of mach 1.7. These are estimates from aerospace engineers and other external forum users not me.
And yes, it can exceed mach 1.7 in supercruise handily.
I’d hazard the EJ200 performs 0.81 lb/lb-f hr at high subsonic cruise and would have to push itself harder and with more consumption to supercruise. As stated in the earlier document the 0.4 bypass ratio engines needed an upper temp limit of 2150K and a lot more fuel just to have a supercruise capability of 1.36-1.4M and that was the best they could do for 1995 simulations of their next generation engines.
Okay, thank you that would make sense then.
The flow rates in static conditions will likely be better for the higher bypass ratio engines, this is expected but the dynamic mass flow rate in supersonic conditions and the other factors I discussed when describing the F119 are not being considered. For the aforementioned reasons in the post you replied to, the higher bypass ratio by nature requires higher SFC and Thrust to supercruise which obviously harms efficiency and lifespan especially if the temp limit is being extended for this reason.
Airframe drag at required speeds must be overcome, that thrust requires high exhaust velocity, high difference in exhaust velocity to free stream airflow indicates high SFC and low efficiency. The larger bypass ratio is not conducive to efficient super cruise capability. There are no efficient supercruise capable aircraft with a bypass ratio larger than 0.34 without some form of variable bypass.
A modification of that engine allows the next gen Gripen variants to supercruise handily and quite efficiently.
Unlike the Phantom, the Super Hornets inability to supercruise is not the fault of the engine. The Phantom was quite an absurd comparison as the British did have a raw turbojet powered aircraft that could supercruise at the time, just not as efficiently as say a F-22. Naturally that is just a generational engine difference but a testament to the performance of the Lightning at the time. The F-106 from America could also supercruise up to 1.5 mach but this wasn’t efficient either.
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