F-16.net

Newbie Joined: Jun 08, 2007 Posts: 11 Status: Offline

No problem at all. As to superior supersonic agility. All NG Air Dominance platforms have been designed with this in mind, from the F-22A, and the Eurocanards to the J-10. ''Cranking'' as Paul Metz called it is an important aspect of the BVR game thats employed by the Raptor and the Typhoon. It can be used as an offensive tool when the aircraft is LO/VLO or the aircraft is employing a long range missile such as Meteor or supercruise assisted AMRAAMs. The fact that the EF gets off the first shot vs a legacy design from the Meteor/LO RCS, means it can use its supersonic agility to crank and get out of the area before the its opponent can get the EF in its weapons engagement envelope. The NG designs maintain a lot more energy while turning at supersonic speeds, this means if the Typhoon cranks away it can retain a lot more speed than say a legacy aircraft can. Therefore the EF may beable to evade the enemies engagement envelope entirely or if not any return shot from the legacy aircraft will have to combat a jet that has vectored out of the engagment zone with a lot more energy then if it was an aircraft of the teen/teenski series. Contempt of engagement.

F-16.net Sponsor

Quote:

Couple of things to consider would be cost of ownership.

Excellent point. F-15 and the various avionics bolt ons like AESA are a known quantity. Time will tell with Tiffy. I especially wonder how maintenance free their new AESA radar is going to be. The nice part about the F-15 is that the R&D for it as well as the goodies are already paid for. Too band Europe put so much emphasis on a jobs program instead of rational weapons procurement.

Quote:

The AIM-120-D doesn`t exist except as a test missile so no F-15`s are carrying them right now. Production is scheduled for December 2007 AFAIK.

Actual IOC should be early fall and full rate production 12/07. Still a lot sooner than Meteor which everyone seems to include when comparing EF to other fighters. Meteor will be entering service around 2010.

Two excellent articles from DID.

http://www.defenseindustrydaily.com/200 ... /index.php

http://www.defenseindustrydaily.com/200 ... /index.php

First article has a good summary of AIM120Ds improved capabilities over the C7.

The second article is particularly interesting in it’s comments in the Meteor section on how the Meteor was designed to allow the EF to overcome it’s shortcomings and be able to defeat late model su-xx.

Quote:

I don`t think I will get ANY argument that the Typhoon has a MUCH smaller RCS than ANY F-15,

True when clean, but maybe not enough to matter when loaded with ordinance. Secondly APG-63 is a more powerful radar. This advantage will only be increased with the addition of a third generation fighter AESA radar.

Quote:

These HOB missiles still have engagement cones that you can maneuver to stay out of so I think maneuverability is still an important factor.

Eventually HOBS is going to get you. Maybe not the first shot, but the second one when you are out of energy.

Quote:

If maneuvering a modern airplane wasn`t important, you wouldn`t see TVC on the Raptor or late model MIG 29s`

Maneuverability is all the Mig 29 has. TVC on the Raptor is mainly for high altitude maneuverability.

Quote:

is going to SEE an F-15 before Typhoon gets seen,

Not when the F-15 has an AESA it will not.

Quote:

NO F-15 late model or not can cruise @ M1.4 with weapons.

M1.4 for a short time, at a certain altitude vs M1.2 or so for the same (maybe not since the F-15 has more fuel) short time at limited altitude. BAE decided to rewrite the supercruise definition now most all planes fit the bill. Only true supercruiser is still Raptor. Everything else is marketing hype. EF folks should say something like highest dash speed in military power because they certainly do not supercruise to any tactically useful extent.

Quote:

The addition of Meteor and AIM 120-D will cancel each other out

See above, by the time EF gets Meteor, AESA will be ubiquitous throughout the fleet of F-15s. Also by the time Meteor is fielded what makes you think that the successor to AIM-120D won’t be?

Quote:

To quote Jon Lake:
''"Late model F-15s with AESA, AIM120D, and HOBS" still have an RCS the size of a barn, still can't supercruise, still can't match the latest unstable fighters for agility, still have inadequate supersonic agility and still have a mediocre MMI.

See all of the above as to why both you and Jon are sadly mistaken. I think Jon’s nationalism is getting in the way of his objectivity.

Quote:

If you read what RAF crews have to say about Captor and how it outperforms APG-63 even with its smaller size; it will be interesting to see if the AESA versions of it hold much of a perfomance advantage if any over the CAESAR.

What are they supposed to say? Are these RAF aircrews conversant with all of the late model APG-63s capabilities. We have heard a lot of BS opinions and unsubstantiated “stories” from the other other side of the pond. Eventually, none of them stands up to any scrutiny.

Quote:

The fact that the EF gets off the first shot vs a legacy design from the Meteor/LO RCS,

The Super hornet is LO also and it has an AESA radar which is far superior to Captor. Tell me who gets the first shot off again? Oh and the AESA is in the fleet now and will no doubt be improved between now and 2012 or so when EF gets one.

The AESA version of the APG-63 carried on the eagle is far more capable than any radar on EF now or contemplated in the future. By the time Meteor is fielded in 2010 the successor to the AIM120D will be ready. Again so who gets the first shot?

Welcome to the board LM.

Elite 1K Joined: Aug 01, 2006 Posts: 1003 Status: Offline

Quote:

M1.4 for a short time, at a certain altitude vs M1.2 or so for the same (maybe not since the F-15 has more fuel) short time at limited altitude. BAE decided to rewrite the supercruise definition now most all planes fit the bill. Only true supercruiser is still Raptor. Everything else is marketing hype. EF folks should say something like highest dash speed in military power because they certainly do not supercruise to any tactically useful extent.

The SU-27/30 with AL-31 engines does Mach 1.22 cruise on dry thrust according to the Russians in "light A2A" configuration. No specifics on stores, fuel load or altitude.

The F-15C does ~M1.2 with the conformal missiles only, F100-PW-220 engines and the FAST pack conformal tanks. Read about that YEARS ago (circa ~1990 or thereabouts; before GWI) in an article about Eagles at Elmendorf -- that was when the -220 was new! Not sure if they removed the two wing pylons, but I doubt it. This is before the advent of the 29,000 lbs PW-229, besides F-15Cs in US service do not have the -229 except of a couple of research aircrafts.

Marginal supercruise has always been around and has always been the norm for fighters. What has changed is that with the advent of the Raptor, everybody seems to want to stake a claim for "supercruise" capability. When the Typhoon, Rafale or Gripen was being developed there wasn't one word about supercruise. Now they all claim it no matter how marginal it may be operationally -- this is especially true of the Rafale and the Gripen. Meeting the "definition" of supercruise means very little tactically, what is meaningful is how fast the aircraft can go on dry thrust compared to the legacy platforms. In the case of the Raptor it's ~50% faster and with full weapon loads.

Elite 1K Joined: Jul 26, 2005 Posts: 1455 Status: Offline

The only real manitenance issues I have read about are spares shortages such as LRUs`. That was early last year, spares issues hit every new jet but it`s availability has been just excellent.

AIM-120-D still ISN`T being carried , so yes, let`s include Meteor. Meteor has already been funded for Typhoon and rounds ordered by MOD.

I think you may be taking too much out of the second article.... The Meteor is a natural progression for big range AAMs and a competitor to Raytheon`s dominance in the market place. Yes, the Meteor will compliment Typhoon as it will enable the Tiffy to "reach out and touch" the opposition, without stealth, it is a sensible addition. If having no VLO technology is a shortcoming, the F-15,16,18 have the same problem.

On manoeuvrability, Raptor has TVC for manoeuvrability Hi` and Lo`, period, as well as massive control surfaces, it was built for manoeuvrability across it`s whole envelope IMO. So, somebody thinks it is still important for a stealthy aircraft to be able to turn and burn.

Thumper wrote:

M1.4 for a short time, at a certain altitude vs M1.2 or so for the same (maybe not since the F-15 has more fuel) short time at limited altitude. BAE decided to rewrite the supercruise definition now most all planes fit the bill. Only true supercruiser is still Raptor. Everything else is marketing hype. EF folks should say something like highest dash speed in military power because they certainly do not supercruise to any tactically useful extent.

M1.4 for a short time? Links please? What is a short time in your opinion? You just don`t know and are assuming. In the presentation to the Norweigian government for Tiffy , there were two range areas covering the North Sea/Atlantic from air bases in Norway, one for supercruise and one without, they were significantly different, suggesting that Typhoon has "meaningful" SC ability. In the Singapore flyoff, supercruise was demonstrated on demand in hot humid conditions for a loaded jet.

On SH AESA,V CAPTOR...

Toan wrote:

A UK test pilot declared that the maximum Air-to-air "tracking range" of CAPTOR radar is "significantly longer" than the 100 miles / 161km. (Source: AFM magazine 05/2004)

The same test pilot declared that with the help of Meteor AAM, the EF-2000 could attack the multiple aero-targets (up to 8 targets) as far as 200km away at the same time theoretically. (Source: RAF magazine 06/2004)

During the test, the CAPTOR radar showed the capability of tracking up to 20 air targets (F-4 and Mig-29) simultaneously 160~185 km away and then automatically identifying and prioritising them. (Source: EADS)

The SH is NOT "LO", some commentators have suggested that it was a waste of time and money trying to reduce the frontal RCS of the Hornet because when you hang weapons on it, it`s still a big `ole radar reflector.

Boeing`s reply was that giving the SH a lower frontal RCS would enable the SH`s active countermeasures to work more effectively.... Shall we toss a coin as to who sees whom first? Typhoon users would feel warm and cosy if all opposition underestimated the CAPTOR the way you do! Laughing

Newbie Joined: Jun 08, 2007 Posts: 11 Status: Offline

Thanks for the welcome Thump.

Underestimating Captor is not the best thing to do, nor is underestimating the potence of the Eurocanards vs the latest teen(ski) versions. It is one of the best M-Scan Radars in the world for its size, some journalists have called it a 'world-beater'.

No its probably not in the same class as an AESA-79 or the AESA-63. But that does not mean CAESAR wont be. Nor does it mean Captor in its current form is not capable of aiding EF in a first shot vs the upgraded F-15s and F-18s.

Nor do we know if the replacement of the -120D will be up and running by the time Meteor is in service.

The EF is not in the league of the Raptor when it comes to SC, but it does offer an operational SC advantage over jets like the F-15. Eurofighter GmbH uses its definition of 'clean', which is 4 Meteors 2 Asraams and an external tank(I am not sure about this, but I will find out), when it talks about the EFs SC capability. Mach 1.2-1.4. Mach 1.5 with no externals and a half tank of fuel.

Enthusiast Joined: Sep 27, 2006 Posts: 67 Status: Offline

dwightlooi wrote:

checksixx wrote:

You can't be convinced that you NEVER factor in R&D to the end user cost? Okay, but its flat out wrong to do so. Point in fact, as you said, the Raptor is only slightly more expensive than the Typhoon. All the numbers are there, just look at them. RCS expense is NOT a factor with the 22...trust me...its not a Nighthawk.

Let's get the numbers out and you guys can decide what is cheap and what is not.

The F-22 is currently about $130 million a piece to build. Realistically even at full line capacity is is probably ~$100 million. That is the cost of extra Raptors for the USAF. Period. R&D is spent and non-refundable.

The build cost of a Typhoon (excluding R&D) is probably around
$60~65 million. That'll be the cost of additional orders by the member nations who originally paid for its development.

So yes, the Raptor is about twice as expensive. But no, it is not astronomically expensive to buy more Raptors. It is only very expensiv compared to the build cost of the F-35 which is around 1/3 as much.

The Raptor is almost twice as large too... 24,500 lbs vs. 40,000 lbs.

Enthusiast Joined: Sep 27, 2006 Posts: 67 Status: Offline

Quote:

No its probably not in the same class as an AESA-79 or the AESA-63. But that does not mean CAESAR wont be

CAESAR wont be up with the 63 because its about half the size.

Elite 1K Joined: Jul 22, 2005 Posts: 1088 Status: Offline

boff180 wrote:

The big test is July.... a certain far eastern air force is deploying to an RAF airbase in Lincolnshire with 6 highly agile thrust vectored aircraft for 2 weeks and playing with the Typhoons from another very near-by RAF Lincolnshire base.

Big plus being they are also taking part in two airshows while they are here... one of them as part of the flying Very Happy

My cameras going to get worn out this year!

Andy

I wonder if we'll hear how crappy the RAF and Typhoon are when the IAF asks them to fight at a four to one disadvantage, no active radar missiles, and then wins? Twisted Evil

Elite 1K Joined: Aug 01, 2006 Posts: 1003 Status: Offline

LmRaptor wrote:

Eurofighter GmbH uses its definition of 'clean', which is 4 Meteors 2 Asraams and an external tank(I am not sure about this, but I will find out), when it talks about the EFs SC capability. Mach 1.2-1.4. Mach 1.5 with no externals and a half tank of fuel.

I am not so sure about this. I am not calling you a lair, but I have not seen anything from Eurofighter or BAe to that regard with those numbers. Also, there is nothing "clean" about 6 AAMs and a fuel tank hanging in the airstream and it will make more sense (from a marketing standpoint) for them to quote a figure with just the missiles and not the tank -- which will be undoubtedly higher. Lastly, I find it very difficult to believe that the addition of an external tank (forget about everything else) makes a mere Mach 0.1 difference in speed attained. This was not the case with every other fighter. Typically it is more like ~15%. An F-16 for instance tops out at about ~1.7 flat out at high altitudes just from the external tank and an F-18 goes down to about Mach 1.4~1.5 with it.

Newbie Joined: Jun 08, 2007 Posts: 11 Status: Offline

I have just done my search. I found out what I put in brackets on my last post. I was not sure about the tank, and it was indeed incorrect. What EF GmbH regard as a 'clean' configuration, is 4 Meteors and 2 Asraams. No tank. So the SC figures are Mach 1.2-1.4 in the EF GmbH 'clean' configuration.

It can achieve a top end SC Mach figure of 1.5(on current engines) apparently with half a tank of internal fuel, in a clean configuration(be it the EF GmbH 'clean' config or a completely clean config with no missiles I am not sure, but I will find out).

Quote:

AIM-120-D still ISN`T being carried , so yes, let’s include Meteor. Meteor has already been funded for Typhoon and rounds ordered by MOD.

We where having such a good debate Snypa and then you come up with the above. Where oh where is the connection between a missile that is still very much under development that at the EARLIEST will be in production in 2010 with one that is low rate production NOW. Yes Snypa now. The first batch of production missiles are being produced now and will be complete Oct 07. LRIP missiles are undergoing operational testing IE out in the fleet NOW. The first full production missiles will be fielded in December 07. How can you compare the two? By the time Meteor comes out the AIM-120D variant will have undergone several upgrades and if history is an accurate indicator of future events will be a far more capable version that that fielded this year. So again, there is a big difference between a missile that will be in regular use in the fleet by the end of this summer and something that will not be fielded for at least another 36 months.

You see the problem with these arguments as with most concerning the tiffy is that we are talking about capabilities it may have in the future and comparing it to capabilities of today. No one is taking into account the fact that LM, Boeing, Raytheon, etc will not be sitting on their hands while all this wonderful technology is invented again, this time in Europe.

Quote:

M1.4 for a short time?

Link please. BAE, the eurofighter consortium and unnamed airforce sources are not reliable links. I bet F-15 does M1.2 for longer than EF does M1.3. The reason is simple. It carries a lot more fuel.

I direct you to some of DLs posts on the subject. “supercruise” on EF is marginal. A more accurate representation is that it has the highest dash speed using military power.

Quote:

The SH is NOT "LO", some commentators have suggested

It’s a lot more LO than EF. In fact calling it LO is more accurate than saying EF supercruises. Every bit of radar reduction reduces the range that a radar can lock on to you. LO is never a waste. I would also remind you that the pylons can be removed and the SH still carries two slammers conformally. SH may also get stealth pods. Also don’t forget all the work that has gone into AESA. Don’t be surprised if you see an AESA radar on future versions of AMRAAM. That will decrease the missile’s FCS.

Quote:

Typhoon users would feel warm and cosy if all opposition underestimated the CAPTOR the way you do!

You mean son of blue vixen, a 30 year old design. I think some on your side of the Altantic are guilty of marketing hype.

Quote:

The EF is not in the league of the Raptor when it comes to SC, but it does offer an operational SC advantage over jets like the F-15. Eurofighter GmbH uses its definition of 'clean', which is 4 Meteors 2 Asraams and an external tank(I am not sure about this, but I will find out), when it talks about the EFs SC capability. Mach 1.2-1.4. Mach 1.5 with no externals and a half tank of fuel.

No one but eurofighter is saying this. It barely reached M1.3 in the Singapore flyoff. Say if it’s so good how come Singapore chose the updated Eagle? How come Australia chose the SH? Why did it lose?

Fact is the EF is a good 80’s design perfected in 2000. It has no real advantages over 4th gen jets and as currently configured is no match for updated 4th gen jets. It is good for two things.It is a European jobs program and it cuts in to Boeing’s margins.

Elite 1K Joined: Jul 26, 2005 Posts: 1455 Status: Offline

Thumper my friend Cool

I am enjoying the debate but I think we won`t agree on much but that`s ok Wink

If you can tell me that Alaskan F-15s are carrying fully operational AIM 120 Ds` and APG-63 v3, or even show me a picture then I will be happy Laughing

Yes of course the "D" is closer to an IOD than Meteor, but this discussion drifted over to capability of F-15 NOW and Typhoon NOW. Am I splitting hairs? Probably!

Thumper wrote:

Link please. BAE, the eurofighter consortium and unnamed airforce sources are not reliable links. I bet F-15 does M1.2 for longer than EF does M1.3. The reason is simple. It carries a lot more fuel.

I direct you to some of DLs posts on the subject. “supercruise” on EF is marginal. A more accurate representation is that it has the highest dash speed using military power. Link please. BAE, the eurofighter consortium and unnamed airforce sources are not reliable links. I bet F-15 does M1.2 for longer than EF does M1.3. The reason is simple. It carries a lot more fuel.

I direct you to some of DLs posts on the subject. “supercruise” on EF is marginal. A more accurate representation is that it has the highest dash speed using military power.

Ok, the F-15 carries more fuel, but there is so much more to it than that.
Amongst them, aerodynamics, the Typhoon has a much slicker shape than an F-15 and is 20 years more advanced, the EJ200 engines on Tiffy are more modern,fuel efficient designs than the older engines on the F-15, the Tiffy is smaller and lighter than the F-15, all just some factors in the equation of fuel usage. To say that the F-15 can supercruise longer @M1.2 than Tiffy can @M1.3/4 based on the amount of fuel is a bit of stretch don`t you think?
The Eurofighter team are pushing the Typhoon with a meaningful supercruise capability, do we assume they are lying to every potential customer? we don`t know the exact figures for the F-22 OR Typhoon and we won`t for a long time

Who said the F-15 can supercruise anyway? With weapons and fuel tanks? I would bet that it simply cannot.

With all due respect to DL, he ain`t an authority on Typhoon supercruise capability any more than you or I Wink

You also say that BAE or Eurofighter consortium are not reliable links. Are they any more reliable than LM or Boeing press releases? I think not. We don`t have access to official air force documents that we can post so all we have are the brochures.

I will direct your attention to a Flug Revue article of vintage 1996 in which Mr Derek Reeb, then BAE chief test pilot says..
and I quote;

"Even with the lower thrust RB.199 engines, used in the DA1 and DA2 prototypes, the Eurofighter has a good performance, says Reeh. He is also sure that the EF2000 with the EJ200 turbofans and six missiles will have a supercruise capability"

Seems BAE have been talking supercruise for eleven years? I am also reposting the PDF from the Typhoon sales push to Norway. Note the supercruise radius from Norwegian air bases compared to non-use of cruise.
http://morisson.thomas.free.fr/Eurofigh ... bility.pdf

Thumper wrote:

t’s a lot more LO than EF. In fact calling it LO is more accurate than saying EF supercruises.

Now, we just don`t know that do we? SH had it`s RCS reducing efforts "bolted on", the Typhoon design evolved with RCS reduction.
You can`t turn a older non-LO jet into a LO jet by painting it with RAM or tweaking inlet shapes. I agree that any reduction in frontal RCS is a plus but the SH is just NOT a LO jet and neither is the Typhoon. They are both "LOWER" observable, not "LOW observable".

Thumper wrote:

You mean son of blue vixen, a 30 year old design. I think some on your side of the Atlantic are guilty of marketing hype.

Thumper you were doing ok until that!! Razz

Blue Vixen was a SUPERB radar which went into service in the nineties, not the seventies...Blue Vixen was the FIRST radar built from the outset to be specifically used with the AMRAAM. You must be thinking of Blue Parrot or Fox, which were much earlier radars for Sea Harriers, or you were just being mischievous!

In Singapore, Typhoon demonstrated supercruise WITH weapons and a fuel tank EVERY time it was called upon, the Rafale failed completely and NONE of the other aircraft even claimed to be able to supercruise, including F-15s.
Typhoon wasn`t chosen because of the immature A2G suite, period.
Typhoon also won ALL of it`s DACT engagements against several types including a memorable 1 V 3 against F-16s. NO other contender managed that.

Typhoon is a viable jet against all other 4th gen` jets , can out-turn them and can "crank" better than any of them!! (That`s a great term LM!).

Forgive my manners LMRaptor, a big hearty welcome to the forum mate Wink

I have to agree with Thumper and DL when they say the Meteor shouldn't be included in the argument as the Meteor won't be exclusive to the Tiffy. At first it maybe the only fighter to operate it but it certainly won't be for its lifespan.

Thumper3181 wrote:

Link please. BAE, the eurofighter consortium and unnamed airforce sources are not reliable links. I bet F-15 does M1.2 for longer than EF does M1.3. The reason is simple. It carries a lot more fuel.

I direct you to some of DLs posts on the subject. “supercruise” on EF is marginal. A more accurate representation is that it has the highest dash speed using military power.

I can't think of an BAE/EADS source on this but I've heard RAF pilots mention the supercruise capability in various interviews for documentaries. I'll try and see if I can dig up any interview that mentions this (off to youtube Very Happy

)

Also if you know anything about aerodynamics you'll remember the mach number vs drag coefficient graph. The drag coefficient will peak at mach 1, so the closer you are to that speed the more drag you will experience. M1.2 on a full tank seems a little far fetched for an F-15 in level flight, but a Tiffy at M1.3-1.4 will be experiencing far less drag than at M1.2. So the reason isn't so simple, don't make the assumption.

Thumper3181 wrote:

You mean son of blue vixen, a 30 year old design. I think some on your side of the Altantic are guilty of marketing hype.

You really underestimate Captor. Captor has an excellent range and the advantages AESA has over it are more in other areas than range (such as multi-tasking).

Thumper3181 wrote:

No one but eurofighter is saying this. It barely reached M1.3 in the Singapore flyoff. Say if it’s so good how come Singapore chose the updated Eagle? How come Australia chose the SH? Why did it lose?

Fact is the EF is a good 80’s design perfected in 2000. It has no real advantages over 4th gen jets and as currently configured is no match for updated 4th gen jets. It is good for two things.It is a European jobs program and it cuts in to Boeing’s margins.

There are many reasons why an aircraft loses, and its not all down to performance. Politics plays a part, the aircraft specifications desired and not to mention reluctance of a nation's air force of changing from a tried and tested exporter to a new one (In this case the US to Europe).

Let me explain the export bit. Say you run an IT company, and you have been running Microsoft OS's since your company was established. If there hasn't been any major issues/problems the chances are that your going to stick with Microsoft, because you know what your getting and you can be confident that a new OS will be as successful as the old one. A change would result in a risk, and why take the risk if there is no need for it. Simply a lot of countries who have opted for the F-35 over the Tiffy have been operating US hardware before and they know it works. They know the procedures inside out for dealing with problems/parts/advice and they know the reliability. So unless there has been problems, they will likely stick to the US for their military hardware. I'm not saying this is the only reason, but it is certainly one of the reasons for selection.

Remember also the Tiffy has not been in service long, so yes there are bugs to iron out, but the RAF are happy with the well needed replacement, its is an extremely capable aircraft and it will do what pretty much all air forces need it to do. It was an aircraft designed for the cold war, much like the Raptor. The cold war ended abruptly and we still have these aircraft. Their existence in todays world is questionable but the need for a new front-line fighter replacement in the USAF, RAF and other NATO air forces is not.

Re: Singapore, one other point of note... typhoon was the only aircraft able to reach supersonic speeds within Singapore airspace! Both Rafale and F-15 had to turn and abort or enter other airspace(with permission) in order to breach the barrier. The big plus Typhoon even did this in supercruise, the others were using their burners. (all instances all aircraft with an air intercept combat load).

Rafale IS capable of a sort of sudo-supercruise as is, I believe the F-15C HOWEVER it cannot breach the barrier on dry power, they must initiate reheat in order to breach the barrier then can return to mil power. Currently, only the F-22 and the Typhoon can truly supercruise without touching the burners.

Andy

Elite 1K Joined: Aug 01, 2006 Posts: 1003 Status: Offline

Quote:

Also if you know anything about aerodynamics you'll remember the mach number vs drag coefficient graph. The drag coefficient will peak at mach 1, so the closer you are to that speed the more drag you will experience. M1.2 on a full tank seems a little far fetched for an F-15 in level flight, but a Tiffy at M1.3-1.4 will be experiencing far less drag than at M1.2. So the reason isn't so simple, don't make the assumption.

Actually, the chances of an aircraft being less draggy at Mach 1.4 vs the same aircraft at M1.2 is for most intents and purposes zero.

Characteristics vary with shape, but in general an airfoil has relatively constant Cd until the critical mach number. Usually this is between Mach 0.85~0.95 or somewhere thereabouts. It then rises -- reasonably at first then spikes for a very narrow ~Mach 0.05 band and decreases again back to a higher but again relatively constant level. This is why nobody flies at Mach one. They either do it at <0.95 or >1.05. But, by about Mach 0.1 pass the peak the spike is pretty much gone.

That is one thing. Thats Cd. But DRAG IS NOT Cd. The drag force is some constant (determined by half the fluid density times the sectional area) times the velocity squared times the Cd. In other words even if your Cd is lower at a higher speed, unless it is exponentially lower, your actual drag force is going to be higher. Most supersonic aircrafts have a Cd that spikes, stablizes at a higher level then slowly increase or slowly decrease very gently. In all cases, it is draggier as speeds increases once past that transonic spike. In fact, because velocity is squared in the determination of drag force, the drag curve is exponential and the sonic spike masked into a mere "hiccup" in many cases.

F-16.net

Forum: F-22A Raptor

Interesting "thrashing" of the Typhoon