SchorschThe recent article ‘Tu-160 with plasma stealth skirts hull, or something like that’ brought up the dicussion of emergency ready fighters, which got me thinking. How many nations still employ aircraft for round the clock, hot pad alert status, ready to be deployed within a few minutes notice??, as was the case with many NATO and WP air forces throughout the cold war. Additionally, out of those countries which still have emergency interceptors online, how many aircraft do they employ?, and does this amont of aircraft still provide a credible deterrence to enemy incursions of airspace in this modern age?.
P.S Also would be interested to know what kind of air defences (SAMS, EWR, etc.) that countries still have
Since 9/11 most nations have re-understood the need for Quick Reaction Alert (QRA) fighters. But these are not intended to fight Russian bombers.
A nation can not realistically defend itself against aircraft flying fast and low level from international waters, at least it cannot guarantee that no 2hostile2 aircraft crosses the coast line.
SchorschTo put this whole on more scientific base, we can ask what exactly defines the take-off weight of an aircraft. That is:
– operating empty weight
– weight of fuel
– weight of payload (we consider gun ammunition as payload, but not the gun itself)
The payload has increased. A load of 4 MR-AAM, 4 IR-AAM, pylons and 600 rounds 20mm ammunition easily exceeds 1.5t. For a fighter aircraft we can assume that payload factor is hardly more than 0.075, that is: 7.5% of the take-off weight is actual payload.
A load for a Sabre weights considerably less. A Gnat was supposed to have 2 20mm cannons with ~100 rounds each, payload in the vicinity of 200kg.
That alone sets the practical weight in an area where no Gnat ever goes.
The fuel: if we consider similar and scalable engine technology, the range becomes a function of the fuel fraction , that is the amount of fuel relative to the gross weight. For fighters a fuel fraction of .3 is considered a good mark (internal fuel).
Finally we have operating empty weight. Above methods pretty much imply that no matter what we do, the aircraft gains weight with payload. That is not entirely correct, payload and fuel factors are taken from experience. There is no physical law saying that higher or lower numbers are impossible. We finally arrive at the minimum aircraft weight for a given mission. There we need to look at scalable objects, that grow with the demanded performance (for example the wings, engines, landing gears, fuselage). A jet-powered RC-model pretty much proves, that a jet can have a take-off weight of 1kg.
But several items are not scalable: the pilot, the ejection seat, a cannon, fire control avionics, some systems (or something ordinary as a landing light). With the advent of jet-powered aircraft we suddenly needed air pressurized cockpits, Mach meters, more advanced aiming devices, better radios and ejections seats. That alone drove the weight of a functioning cockpit, that the minimum aircraft around it hardly made it below 5t.
Some exceptional designs were substantially lighter. One thing that needs to be considered: the structural weight for all that payload, fuel and equipment to stay aloft (let’s call it the airframe) is not a linear function of the rest’s weight. It grows faster. So, if I reduce my payload/fuel/equipment by 10%, I can save 20% on structural weight, leading to more savings in fuel & equipment. If I find a sweet spot where a working systems emerges, I can call it a design. Such designs normally make it to the record books but have a distinct lack of growth potential and generally most of the time carry considerable compromise.
Schorschsir,,,,,you are so wrong the mig-25 can easily achieve above mach 2 at 1000 meters,,i have done it so has all IRAF mig 25 pilots ans the soviet pilots too, i suggest you go read about it more,,and get some flying time on a kite before claiming i am not a pilot,,,if what your saying is true then buildeing 25 is pointless! dont you agree?
Not really. Mach 2 at 1000m are consistent with an airspeed of 1250 kts or (as the Russians use km/h) 2315 km/h. Easily more than double the allowed speed limit for a MiG-25.
See below the flight envelope of a true fighter.
[ATTACH]166070[/ATTACH]
The Phantom has a clear speed advantage below 10000m/33000ft.
SchorschThe aft body design of the MiG-23 looks solid and state-of-the-art, while that of the J-8 looks like a big piece of disaster. If the copied, they obviously missed the mark.
Aft body design has very noticeable effect on transonic and supersonic drag.
SchorschHow about some practical claims, the FAB is in need of endurance at first. 😉
With 4-6 AAM and 3 drop tanks time on station shouldn’t be any worse than that of a Rafale or a Typhoon. The Rafale or Typhoon offer better performance with 4-6 AAM I think, but I doubt supercruise is truly demanded by the FAB. If so they would be stupid to put the only aircraft truly capable of it from the list.
SchorschWhich goes back to the argument, how much more are people willing to pay for a small percentage improvement or even an enhanced option (such as carrying more AAMs) when they will rarely be used to their full potential. If the Gripen can offer 80% of what the F18 and Rafale can offer but at 70% of the purchase and operational cost, which option becomes more tempting for Brazil. Although obviosuly there is always the politcal game at play where the most obvious choice is not always made….
—–JT—–
I doubt there is any true disadvantage. But it depends. If the Brazilian AF considers extra missiles in the air as advantage it may pick the Rafale. Fact is that Brazil does not await the onslaught of hundreds of fighters and any war versus an enemy in the north would not require total air domination (rather constant attrition).
I think it would be a very interesting guessing game on how many occasions an aircraft have used more than 6 AAM in one engagement (duds don’t count).
Schorschthats almost depressing :rolleyes:
Why? Because we haven’t increased the speed by 5% a year?
Guess what: if the passengers today would be willing to spend the same amount of money (in terms of buying power) as they did then for flying across the Atlantic, well, you would see Concordes all over.
Today I can afford a flight and the last death was I think ten years ago (Swiss MD-11), during that time hundred million people if not more have crossed the Atlantic.
I would say it is as good as it could get.
Safe, affordable, comfortable: a people’s product.
SchorschThe J-8II never has had direct relation with the Su-15 beyond having the same engines.
Which is quite a lot.
Inspecting the J-8II you find the inlets, radome and ventral fin are a direct copy of the MiG-23 and that si a fact since the Chinese adquired some MiG-23MS from Egypt.
MiG-23 and Suchoi 15 were not designed on two different worlds. Both MiG and Sukhoi benefited from research done at TsAGI and other. MiG-23 and Sukhoi 15 are very comparable in used technology and overall performance criteria, apart from the swing wing for better take-off performance for the MiG. The differences grew when the MiG-23 became more like a fighter. The PVO finally operated MiG-23P and Su-15M alongside.
SchorschWould you mind tell me how to convert the G limit to turn rate? :confused:
Acceleration = Speed² / Radius
For aviation purposes:
r = v²/(G-1)
The “-1” is for the gravity.
If an aircraft has 4g sustained turn performance at 900km/h TAS, the radius becomes:
r = (900/3.6)^2/(9.81*(4-1)) = 2123m
The turn rate in °/sec:
TR = 360° * v/(2*pi*r) = 6.7 °/sec
You can make it direct:
turn rate [deg/sec] = 9.81 * (G_factor – 1) * 360° / (2*pi*vTAS)
G_Factor in g
vTAS in m/s
SchorschThe difference in installed power is felt at take-off and during low speed. With rising speed more and more thrust is coming from the inlet- and outlet-system. At supersonic you can “forget” about the engine. Behind subsonic, the installed thrust-weight ratio is no longer a yardstick. See the performances of a MiG-25 about that. 😉
While the recovery factor really becomes important beyond M1.5. The F-16 has a fixed inlet and doesn’t suffer any disadvantage in transonic regime. While no-one has detailed thrust/drag ratios available, I cannot see how even an F-14D could beat an F-16 in transonic there if we stick to relevant a2a configurations.
Besides, one can buy and operate two F-16 for one F-14.
SchorschNearly all missile bought were never used in anger. When it comes to something true, the cost of a missile is not important either. When fired in anger it has to fullfil a task. Either it do or it is a waste. Aside from “soft-kills” by limiting the movement of the opponent, it is the impact on the pilots of the opponent. Every aircraft can be replaced in short notice most of the time, when a worthy pilot does take several years to train and the related money in mind. By that it is a waste of money to train a pilots for millions over the year, just to loose him inside a cheap inferior fighter.
The PK of every AAM from the 70s was higher than 0.5. But for different reasons most were fired outside their envelope. None will blame the pilots for that, because it is their task to survive for the next mission to be of military use for some time. A dead or wounded pilot is useless. The bill, if the airpower was used in the most effective way will be presented, when the truce is signed.
The cost of an AIM-54 is?
The cost of a Tu-22 is?
The cost of an ASM is?
The cost of an CV is?
The human factor aside.
As long as a AAM does fullfil a usefull task it is worth its money always. It does even justify to buy a usefull number just for the remote possibility of a true combat situation.The AIM-54 does work like a basket ball. The F-14A does launch it to a cone above the intended target. You direct a basket-ball from your base-line just over the basket, when the own seeker will find the basket or your team-mate will do so impact. The AIM-54 diving down from “nowhere” and a power-full blast to bring down big targets can create some panic in a formation of smaller fighters. Even when your RWR screem alarm about an AWG-9 painting you over 100 km away, there is always a possibility that an AIM-54 may be “overhead”. Most time it was not, but such situations are no good for your nerves and your fighting spirit sometimes. 😉
We are looking into a fighter versus fighter engagement, where the CVBG is not at risk. For an opposing bomber equipped with nuclear tipped ASM the cost surely is no consideration, and these targets are less likely to do “missile fishing”.
I guess the Phoenix has its ups and downs in this kind of fighter vs fighter engagements. Disadvantage is definitely cost and weight.
Advantage is range, some fire&forgot characteristics (although only on the very last leg) and its smoke free approach to target. Even if an RWR picks up the Phoenix active seeker, it will be quite difficult if not impossible to spot the missile. And although a really hard turn might trick it, such a turn is unsustainable for most aircraft (I think Phoenix can cope with 6g maneuvering targets), hence the attacked pilot must act a bit like a goal keeper during a penalty.
Today, we see Europe preparing to deploy Meteor, which will have a range approaching that of AIM-54 (albeit with a smaller warhead) and of course the Russians have been working feverishly to develop and deploy air-to-air weapons with ranges substantially greater than Phoenix. Aside from anti-fighter use, these could be used to target AWACS or tankers well outside the range of their defenders’ ability to protect them, making such weapons a true game changer.
Very interesting is that on paper such a missile always wins, but in reality the chance for such shots often didn’t materialize due to rules of engagement or used tactics.
The question is if such conditions do exist now, or if such a missile is basically a paper tiger. When stealthy aircraft oppose each other, the idea of BVR shots becomes questionable in general.
@topic:
I’ll say the F-15A is clearly superior and the better WVR-fighter.
SchorschI’d agree. But then that’s not what typically going on. Packing fuel into otherwise empty space isn’t the horrid idea some seem to think it is. Why make it necessary to carry an external tank when you could simply fill in some of the empty spaces in the airframe THAT ARE ALREADY THERE? Makes no sense at all.
Concur.
SchorschSo why spend the extra $$$ and structural inefficiency for tanks that take into account the overall area rule of the aircraft if it doesn’t need too? Pretty much everybody else (with the exception of the F-5) just sticks to pointy cylinders. Why the exception here?
Tanks make sense.
For basically any mission you have the take-off and cruise-in section, that doesn’t require supersonic speeds or stealthiness. Of course, designing an aircraft specifically to fly supersonic with tanks does not make too much sense, but enabling it to do so enlarges the mission envelope.
When going into combat you want to have the minimum airframe with maximum fuel and weapons. Having an airframe that carries the extra fuselage volume needed for the (then expended) take-off fuel into combat, is not the brightest thing, either.
SchorschYip. Like the Blackburn Buccaneer. Optimized for transonic speeds.
But never broke the wall in level flight. In case of the Buccaneer the airframe was optimized for a small Mach number region.
SchorschInteresting. It does make one wonder why they’d do that given that most fighters just punch the tanks off if they want to go supersonic (particularly strike aircraft). I know there are aircraft that can go supersonic with tanks but they’re the minority and generally those that were designed primarily for air combat with strike being the secondary consideration (see Typhoon). would be interesting if it turned out the F-35 could supercruise with internal weapons and a pair of external tanks. Before some shout “unpossible” remember it’s got as much dry thrust as a late model F-16 in full afterburner.
Most aircraft can go supersonic with external tanks, given they have “supersonic” tanks (an F-4F makes M1.6 with wing tanks and 4x Sidewinder). Of course, that requires afterburner. The only supercruisy aircraft able to do so with tanks is the Typhoon to my knowledge, but currently their are only two supercruise aircraft (and for the other carrying tanks while supercruising is somewhat stupid).
Sign In
