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Jul 04, 2012

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Dfens

Just having a fast missile does not grant you a kill. If you see an airplane with your radar 10 miles away and inbound at Mach 2 or 3, and your radar takes 2 seconds to recognize the inbound has a threat signature, then another second to put the beam back on the inbound which has moved a mile or two between scans on a vector that has yet to be determined, then your radar finally begins to create a track for that inbound at 10 seconds if you're lucky. It next has to complete the intercept equation with the chances for an intercept diminishing rapidly as the distance closes. Now unless your aircraft's nose was within a few degrees of the optimal firing attitude, you have no shot and even if you did, you physically could not react quickly enough to the solution symbology to take the shot.

So now you have to revert to a trailing shot, which means you have to bring your aircraft around for a new firing solution that will be built from scratch as your radar loses target lock. So once you've completed your turn and lost a bunch of speed, then you try to lock up again as the opposing vehicle rockets away. At this point you could shoot a missile with a top speed of Mach 10 and it could not cover the distance between the two aircraft before running out of fuel and dropping to the earth.

Missiles are great for subsonic engagements, but are nearly useless against targets traveling at substantial supersonic speeds, unless they are fired from vehicles capable of closing at those speeds. The faster a missile is, the less effective range it has.

To date all of our fighters have been designed with a capability to go supersonic for short sprints only. This is true even of the F-22 that advertises "super-cruise" but has such a pitifully short range that it's not worth the extra 0.3 Mach and it has to be put into afterburner to even punch through Mach 1.

I'm talking about making fighters that are fast. Fighters that are capable of sustaining Mach 2 to 3 for 1500 miles or more, not just in short sprints. It does no good for a stealthy aircraft to be in a dogfight. If it is in a dogfight, then it is not stealthy as everyone on the opponents side knows where your airplane is ever since the invention of radio.

pat b

DFENS

Certainly I remember the health issues of the B-2 work force where "Security" meant the workers couldn't even get the MSDS sheets on the materials they were using. Now perhaps more ventilation and better air systems might help the crews both Air and Ground, but,
i'm not sure about your overall suggestion.

Fighter design changed when high speed missiles became ubiquitous. The theory being no aircraft could outrun a missile they began aiming to increase high speed manuevering, add EW suites and countermeasures and flying low to the ground as well as decreasing radar profiles.

the issue is can these become overcome in a large aircraft? Certainly fighters have become much larger then their WW2 and 50's counterparts. the F-88 and 102 are much smaller then the F-14 and F-22. The F-14 was jokingly called the Tennis Court and the F-22 with it's 44 foot wingspan is no petite aircraft.

Are you proposing that we try and build more like the A-4 with some stealth features like a composite Leading edge and a small little engine and minimal avionics or are you proposing something else?

regards

Pat

Dfens

I don't know a lot about stealth coatings, but I do know that they are applied by robot because they are highly toxic to humans. I'm fairly sure the coatings use a polyimide binder for much the same reason the carbon fiber skin uses a polyimide matrix, that being heat resistance. Given that we know the composite matrix resin causes breathing problems and these could only be compounded by the unknown nasties in the coatings, it seems very "convenient" that no attention is being paid to outgassing as a cause of the pilots' and ground crews' breathing issues.

The issues with aircraft outgassing can be worked around. Certainly if the environmental air were drawn in from a smaller, shorter, dedicated intake made from aluminum instead of composites, feeding an electric or hydraulic powered dedicated compressor it would eliminate most of the contamination concerns. Many of the ground handling and crew concerns could be dealt with by increasing the ventilation around the airplane when hot. That means having some big fans around to keep the air around the airplane moving until it cools down.

Mainly though, I think we really need to reexamine many of the basic assumptions that lead to the design of the F-22 and F-35 as they are. Basically they rely on the lightness and stiffness of the composites to enhance performance but the price of this increased performance is decreased aircraft and pilot survivability. This is the absolute opposite construction philosophy we used in WW2 where our fighters were more robustly constructed, armored, and cheaper than those of our enemies, and won by pilot attrition and pure numbers of aircraft put in the sky.

Instead we make our aircraft light and maneuverable, unreliable and fragile, and unbelievably expensive and rare. Our policies are demonstrated failures by our own hard won experience, and yet they are never questioned. We should be using speed in place of unreliable stealth coatings, and aluminum, titanium, and even steel in place of super expensive and fragile composite structures. Our fighter aircraft should be shaped for stealth and large. They should hit hard and fast and disappear quickly into the distance. Most of all they need to be an order of magnitude cheaper and more plentiful.

Michel

Guess we investigate via autopsy. That should solve the issue. As I said once before (not the O2 delivery issue), but the stealth material is cyanide based and never ever never cures!

pat b

DFENS

Your proposed mechanism involving the composites is a valid concern in my opinion.
Many of the resins used in composites particularly for low radar signature or "Stealth" have unknown biological effects. If it's truly an aircraft materials problem is there a fix?

Dfens

Suddenly everyone forgets about all the problems the F-22 had when it's parts were first being manufactured (by the way, the B-2 had similar problems with its composite parts). Lot's of workers, even engineers in rooms with no openings to manufacturing areas were getting sick from the fumes off the uncured and curing composite parts. Just because the parts have been cured, those chemicals don't just go away. They're still inside the composite matrix waiting for a chance to get out. It's a jet built around 2 huge engines that heat everything and a lot of the problems are late in missions when the jet is hot and parts are outgassing at their maximum. Plus the jet has extremely long intakes which are all made from the problematic composite material. This would also explain why ground crew members are getting sick just being near the airplane. Too many coincidences to believe this isn't an old problem rearing it's ugly head again.

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