miket@brspyr1.brs.com (Mike Trout) (09/15/89)
From: miket@brspyr1.brs.com (Mike Trout) In sci.military Digest Tue, 12 Sep, 1989 Volume 2 : Issue 93 supp@tank.uchicago.edu (Steve Upp) writes: > These [heat-seeking] missles however, have an accurate range of 1 to 4 miles > or so. At that point its likely that the enemy aircraft will see the shooting > aircraft in which time evasive actions (therefore mobility) are required. And dlj@cbnewsh.ATT.COM (david.l.jacobowitz) writes: > Maneuverability is required in the current "age of missiles" just as > much as it was during WWII. And "Michael J. Chinni" <mchinni@PICA.ARMY.MIL> writes: > Since, in dog-fights manuverability is very important (i.e. to attack and to > avoid attack) and the U.S. has learned from vietnam and from various other > countries wars that there will always be dog-fights, we make our planes has > manuverable has possible within the limits of structural integrity and pilot > physical limits. And jln@portia.Stanford.EDU (Jared Nedzel) writes: > But what if that [AIM-9L] misses too (or, what > if you're terribly out-numbered)? Now you have to manuver to get another > shot, either with a Sidewinder or a cannon. In addition, by this time you'll > probably have to manuver to avoid your opponent's missiles. If you can't > manuver with you're opponent, then you're SOL (Sh*t-outta-luck). And craig@june.cs.washington.edu (Craig S. Anderson) writes: > If a pilot has a maneuverable aircraft, he can gain a positional advantage > on an enemy aircraft in order to use shorter range weapons, like infra-red > (IR) missiles or cannon (assuming the enemy is close enough). _______________________________________________________________ All of the above were in reply to the original question of why our planes have to be so maneuverable in this age of high-performance missiles. All the replies were good responses, pointing out various problems with missiles and certain combat situations, and taken together show how dangerous it is to rely solely upon high-performance missiles (despite current USAF efforts to the contrary). Yet I think there is one point that all the above failed to make, and thereby a certain amount of confusion may result. The point is that MANEUVERABILITY, by its strict definition, is really NOT important in air combat. Perhaps what the original questioner was referring to was really PERFORMANCE, not maneuverability. The two are not the same. A strict definition of maneuverability is the ability to change direction. Performance includes far more, and an airplane with good performance does not necessarily have good maneuverability. Consider the following two points: 1. 80% of all airplanes that are shot down by other airplanes never detect their attackers. They never know what hits them. Regardless of whether the attacking plane uses missiles or guns, in these cases the attacker's maneuverability is irrelevant. The important factors for the attacker are speed, firepower, and (most important) crew quality. In only 20% of cases are both airplanes "fighting" each other, and only then does maneuverability come into play. This 80%-20% ratio has held fairly constant from World War I up to the present. 2. There are two wars we can validly study for this purpose: World War I and World War II. Both these wars had relatively equal crew quality and comparable levels of aircraft quality and production for the various adversaries. And most importantly, both lasted long enough, and both involved such total national committments, that many aircraft appeared before the wars ended that had been designed DURING the war, and thus reflected the lessons of those wars. And in both wars, most nations entered the conflicts with highly maneuverable planes--yet during the wars switched to planes that were far less maneuverable. As each war went on, the emphasis switched from maneuverability to speed and firepower. In air combat, speed is life, because stored energy gained by speed can be transferred into whatever maneuver you want. This is why the "unmaneuverable" F-4 Phantom can actually be a good dogfighter if it has a good crew--the Phantom's superior energy (ironically, a factor of its high weight traveling at high speed) can be transferred into maneuvers comparable to those of planes with more maneuverability but less energy. But, in fact, the best fighter pilots avoid dogfights whenever possible. There are too many variables in a dogfight. The more you turn, the more energy you lose. The faster you go, the less you can turn. The object is to attack unsuspecting enemy planes (remember the 80% figure) so ruthlessly that they are destroyed before they can react. The best way to do this is to approach them at high speed (preferably in a dive), hit them as hard as possible, and get away fast, keeping your speed (and therefore energy) as high as possible. Again, this has been the case ever since World War I. Consider two notable fighters of World War II--the Gloster Gladiator and the Me 262. Although these planes never met in combat, they represent opposite extremes of fighter philosophy. The Gladiator's maneuverability, it being a biplane, was infinitely superior to that of the Me 262. In a standard, tight, close-in dogfight, the Gladiator would eventually chew the Me 262 to pieces, despite the Gladiator's weak firepower. The problem is that no Me 262 pilot is going to get into a dogfight with a Gladiator. He's going to blast right by it with his jet-propelled 250-mph speed advantage, blowing the Gladiator to atoms with his powerful cannons as he goes by. (As an aside, during the Korean War two US jet fighters were shot down by North Korean biplanes, when the US pilots made the mistake of getting into dogfights with the pokey but highly maneuverable biplanes.) Note the Gladiator comes from a pre-war 1930s philosophy, while the Me 262 was developed under the pressures of real war. If you don't like such extremes, consider four important nations of World War II who began the war with highly maneuverable fighters and switched to faster, less maneuverable planes. The United Kingdom began with the Hurricane and Spitfire and ended with the Tempest and Typhoon. The USSR began with the I-16 and MiG-3 and ended with the Yak-3 and La-9. Japan started with the Hayabusa and Zero and ended with the Hayate and Shiden. And Italy started with the C.R. 42 and Freccia and ended with the Sagittario and Veltro. In all the above cases, the earlier planes could greatly outmaneuver the newer models. The later planes tended to be big, heavy "hot rods" with tremendous firepower, but poor maneuverability. [Two other important nations don't really fit here, as neither ever emphasized maneuverability, even in the early part of the war. The USA emphasized heavy airplanes that could take lots of damage (which later was easily changed to an emphasis upon high horsepower with corresponding high speed), while Germany emphasized speed, firepower, and innovative tactics.] Similar trends can be seen in WWI (Sopwith Pup replaced by Sopwith Snipe, Nieuport 17 replaced by SPAD XIII, Albatros D.III replaced by Fokker D.VII). The basic point is that good maneuverability is great for defense--but air combat is decided by OFFENSE. If your airplane's sole virtue is superior maneuverability, you're going to be reduced to reacting to whatever your enemy does--assuming you're one of the lucky 20% who detects the enemy coming at you. You'll never be able to dictate the terms of the fight, like the guy with the superior energy can do. About all you'll be able to dictate is which part of your airplane gets blown off. It's true that history shows many cases where highly maneuverable planes came as a nasty shock to their adversaries. Among these were the Fokker Dr.I, Spitfire, Zero, and various MiG jets, all of which had a tremendous maneuverability advantage over their opponents. Yet ways to deal with this advantage were developed, and by the end of their wars these planes were either no longer produced or were easily defeated. Speaking of MiG jets, there's been an interesting trend in Soviet fighter design. The earliest Soviet jets, such as the MiG-15 and MiG-17, were extremely light, maneuverabile planes, but with powerful armament. The next generation, including the MiG-19, MiG-21, and Su-9/11/15, were slightly heavier but had much more powerful engines, keeping a maneuverability level far superior to that of Western planes. Then the Soviets seemed to begin changing to Western-style aircraft that were big and heavy with poor maneuverability. These designs included the MiG-23 and the fast but bulky MiG-25, one of the least maneuverable fighters in history (designed, at any rate, to shoot down the B-70). A little before this the Soviets produced the biggest fighter in history, the monster Tu-28. Now they seem to be emphasizing maneuverability again, although their new designs (MiG-29 and Su-27) are very similar in weight and performance to superb US planes like the F-15 and F-16. And the unwieldy MiG-25 has been resurrected in a two-seat anti-cruise missile version named the MiG-31. Re-examining the original question, there's a certain irony in that US planes have never been thought of as being particularly maneuverable. US fighter pilots were able to get around this just fine in WWII, Korea, and Viet Nam. Nevertheless, the Viet Nam war resulted in a lot of complaints about how US planes tended to be big, heavy, complex, and expensive, while Soviet-built planes tended to be small, simple, cheap, and light (and therefore highly maneuverable). Since then, US design has paid a little more attention to keeping planes light and maneuverable. Heavy planes like the F-14 seem to be less in favor, while the F-16 seems to be well thought of as a trend for the future. The F-16 represents one of the USA's most impressive committments to light, maneuverable design, although the expected Military-Industrial Complex syndrome is continually hanging more bells and whistles on the plane. Still, it appears that at least some consideration to maneuverability will be a part of future designs. Recent advances in engine output give thrust that exceeds the weight of the plane (F-15, F-16, F-18, MiG-29, Su-27, Rafale, Gripen). This provides outstanding performance across the board (not just great maneuverability), giving the fighter pilot a superb weapons platform that he can use for a wide variety of tactics. This is why I think the original questioner really is referring to overall aircraft performance, rather than just the strict definition of "maneuverability". In closing, I'd like to repeat something I've said before in this forum: air crew quality is about ten times more important than aircraft quality. We can discuss airplane maneuverability, performance, and whatnot from now until the cows come home, but it all has little impact in real situations. What we really should be comparing is things like aircrew training, motivation, organization, and ability; those are the criteria that REALLY matter. -- NSA food: Iran sells Nicaraguan drugs to White House through CIA, SOD & NRO. ~~~~~~~~~~~~~~~~~~~~~~~~Michael Trout (miket@brspyr1)~~~~~~~~~~~~~~~~~~~~~~~~~ BRS Information Technologies, 1200 Rt. 7, Latham, N.Y. 12110 (518) 783-1161 "God forbid we should ever be 20 years without...a rebellion." Thomas Jefferson
mmm@cup.portal.com (09/17/89)
From: mmm@cup.portal.com miket@brspyr1.brs.com (Mike Trout) says: > Recent advances in engine output give thrust that exceeds > the weight of the plane (F-15, F-16, F-18, MiG-29, Su-27, Rafale, Gripen). What are the "recent advances"? Could someone please summarize and comment. BTW, I saw on TV some video of the assembly of a cruise missile. One of the technicians was carrying around the engine for the missile. The turbine looked to be about 2 1/2 feet in diameter. What was surprising was the weight. From the way the guy was holding it, I would guess this engine weighs about 25 pounds.
gwh%earthquake.Berkeley.EDU@ucbvax.Berkeley.EDU (George William Herbert) (09/19/89)
From: gwh%earthquake.Berkeley.EDU@ucbvax.Berkeley.EDU (George William Herbert) In article <27295@amdcad.AMD.COM> mmm@cup.portal.com writes: >What are the "recent advances"? Could someone please summarize and comment. Engines with a 10-1 thrust/wt ratio, and better for the next generation (ATF). >BTW, I saw on TV some video of the assembly of a cruise missile. One of the >technicians was carrying around the engine for the missile. The turbine >looked to be about 2 1/2 feet in diameter. What was surprising was the >weight. From the way the guy was holding it, I would guess this engine >weighs about 25 pounds. The ENTIRE missile is less than two feet in diameter. The actual engine is (about) 12" in diameter and between 24" and 30" long. It's a turbojet, can be bought in a derated form from (I believe) Williams Intl. for general aviation use.