Re: Something about the F-22 Raptor

Before the design of the F-22 was finished, its RCS against ALL known radars were established. The USAF knows at what range and what angles the F-22A can be detected by any and all radar, IR and or, electro-optics systems.

One thing that must be remembered is, that during exercises the F-22A has different levels of stealth. It doesn’t fly around all the time completely ‘stealth’d up’! It depends on the rules of engagement (ROEs). The rules of engagement are not always known to the F-22’s opponents. A pilot in a fourth generation aircraft would work hard to get an F-22 into their weapons engagement zone, to make a kill is an accomplishment. There is no need to down play the pilot’s accomplishments by telling them that the ROE’s for the F-22A might include a low level of stealth or performance limits. Such as the F-22 in exercises has been limited to pulling no more than five “G’s”! That way the F-22A pilot has to work to avoid being killed and the F-22’s opponent has some chance in scoring a kill against the F-22.

Re: US SSN torpedoed Kursk?

As far as the torpedo maintaining orientation, the massive computing power and inertial guidance system keeps the torpedo in the most efficient attitude. There is a lot of talk about the ADCAP’s digital computers well, before the digital computers many of the functions were analog when necessary.
The torpedo’s range safeties. Anything within this volume that is detected if the torpedo is searching for a target will be classified as ‘friendly’! Outside the these limits are treated as an enemy.

I’m not so sure that is the case that torpedoes can be loaded into launch tubes in only one ‘way’ with correct orientation of the warhead.

I would imagine so but, either way its inertial guidance would keep it aligned properly.

The Frigate HMAS Torrens (or ‘destroyer escort’ in aussie naval parlance) paid off in 1998

Thank you for the details.

high-explosive unitary warhead of some 650 lbs 293 kg) of high explosive.

I got the photo from a book entitled, “Underwater Missile System” back in the 1970s. I came across the book once at the Stanford University library.

This has nothing to do with upwardsfiring shaped charge warheads.

If you are trying to break the keel of a large carrier, focusing the energy offers greater assurance that the massive network that forms the keel will be broken. Breaking the keel of the HMAS Torrens, an 2,700 ton destroyer escort and breaking the keel of a ship that displaces more than 30,000 tons are two different things.

Re: US SSN torpedoed Kursk?

Interesting! I’ve not heard of an upward directed shaped charge warhead on a heavyweight before. Non-directional warhead seem quite sufficient in breaking a ship’s back. Would a upward firing shaped charge be THAT much more effective to warrent its development?

Just the opposite direction than the Bill, TOW, etc. anti-tank missiles. There are a few pictures on the I-net showing how the warhead being a ‘keel hunter’ torpedo does not impact into the side of a ship but, explodes about 10-ft (3-m) under the keel of the ship, breaking it in half.
One such photo is of a Australian destroyer being sunk with a Mk.-48 torpedo fired from an Australian sub. The other attached photo is of the shaped charge warhead underwater.
When a torpedo explodes under the keel, the force of the explosion will lift up that portion of the ship. As the energy is expended, the remaining gases mixed with the water causes a low density area where the ship settles and because of the low density the target settles far deeper than it normally would. If the back isn’t broken by the explosion, the ship settling in the low density water will cause the keel to break completely.

is it developed with a particular type of target in mind? If so, the torpedo would have to be made smart enough to know which ‘side’ is up and be ‘self righting’, unless it is always loaded and fired with a particular ‘side’ up (‘side’ is a strange term considering we’re talking about a round object.

The torpedo is the smartest missile used! It has re-attack capability if it misses the first time. Some anti-ship missiles have a limited ability to re-attack a target. Think about it, PC boards almost twenty inches in diameter, many of them. That is a lot of computing power.

I would assume that the shaped charge design would be solely for use against subs, whereas creating a large air cavity under a ship with a more normal explosion on ships would make sense.

the large air cavity rising and breaking the ships back.

Just like in the movie, “Crimson Tide”…. the Mk.-48 headed for the Soviet Sierra sub. The torpedo approached from the side, then dipped down and was hit under the keel. Also very similar to the video from Iraq when some insurgents fired a Kornet anti-tank missile from inside a room, through a window at an M-1 tank about seventy-five feet from the house. The missile approached the M-1 then climb above it and exploded.

The Kurst displaces 16,600 tons submerged while the LA class is around 9,000 tons, in a collision of two front ends of a sub colliding, why would people think the smaller sub would fair better. A single hull versus a double hull and the double hull looses? If the USN caused a Soviet sub to sink don’t you think the Russians would have figured out some way for an American sub to have an accident? Once real common sense is injected into the argument is ceases to be a conspiracy.

Note:
The director of that movie offended the RC submarine modelers by exchanging the Soviet the Mk.-48 and the Soviet torpedoes. So the Sierra fired Mk.-48s and the ‘Alabama’ fired a Soviet torpedo. The director felt the Mk.-48 looked more sinister!

RE: Rafale News VII

Facts
Other “scoop” concerning the rafale vs typhoon…This MN pilot already downed a typhoon with a two supersonic drop tank config (for the rafale) in a simulated gun dogfight. It took him three turns to take the advantage.
So he didn’ felt that there was a big gap of performance between the two aircrafts in this area.

I would like to hear more about the ROEs and how the situation developed. Did the engagement start in the heart of one planes envelope while the other was less effective in that speed / altitude range?
There have been so many engagements in which sounded bad for the F-22A getting caught in the gun-sights of an F/A-18 or a radar lock-on by a T-38 and not be able to maneuver away. Against the F/A-18 its pilot broke many rules to get that gun camera footage. In the case of the T-38, for that engagement the F-22A was limited to 5G’s!

Re: F22 lives?!?

the F-22A was neither ready nor fully tested, when the series production did start already and the costly consequences from that.

Actually, no aircraft before has had so many design reviews, had as much computer simulation time, and hours of flying time than the F-22A. (Considering the develop time of the Su-27, the F-22 computer time and flight time was considerable.) That said, having made a monsterous leap in so many technologies, there have been and will issues over looked that will be discovered in time. There is no crystal ball that allows the designers to know and see all…. it is unreasonable to think there would be no problems discovered in time.

the F-22A Blocks built after 2007 did come close to the promises made about that. Now it does make some sense to order that in bigger numbers. Just too late, all the money is in need for the F-35 program to advert a similar disaster. The allocated money for the F-22A program is used up for years and it is difficult to find some new money to bring the few F-22A built to a common standard right now.

The problem with the cost is, those who opposed the F-22 the most, were able to drag out the program with constant reductions in funding, then inflation became a real factor. The very people who opposed the F-22’s program by dragging it out, are the same ones who now complaining most about the cost. The original schedule called for the IOC of the F-22 was to be early in President Clinton’s second term. After the Cold War was over the Pentagon informed LM to plan the program schedule to be stretched out ‘at least’ seven years and the production run would be at least cut in half. To restructure the schedule and cost accordingly.

Re: Speedy Nimitz!

The real question is not, “what is the USS Nimitz Class carriers top speed?” The real question is what is the top speed of the escorts? How fast can the Burke or Ticonderoga Class’ go. As the weather / sea state increases increases, their speed decreases. The submarine escorts can keep up with the Nimitz carriers but, due to the boundary layer of water around the sub, it’s sonar is useless, it is as blind as a bat!

Re: Gripen NG beats SU-35 in a2a

Now, you mentioned continuous curvature stealth. This is exactly the opposite to known principles of radio waves spread. However, designers may have well exploit some “blind spot” nobody was counting on and if you have some more insight into these techniques, I’d appreciate if you’d share them :). Thx.

I do know the leading edges of the B-2 Bomber’s fuselage is NOT straight! It is an arch with a radius of “2,475-ft.”!!! The maximum distance from the arc to the cord that ajoins the arc is 6-in. It was a wild math project to do all the calculations.

It’s kind of a mystery to me, too, but basically it’s a matter of finding shapes that exploit how radio-frequency electromagnetic waves are converted into electrical currents that flow on the surface.

That is exactly what Northrop’s contract “Tacit Blue” was for. The Pentagon/USAF did not want the technical talent of Northrop to be disbanded because they lost the Have Blue competition. Tacit Blue was the contract to keep the team together.

The only case in which F117’s flat belly is in worse position than fractured one, is when it gets illuminated and seen by a longwave radar.

The bottom of the F-117 is canted upward at a 10°, starting at the center-line. Even “if” a radar is perpendicular to an angle on an F-117, it will bounce one or two pulses off the F-117. If the F-117 is in perfect alignment, once it moves another meter or two the alignment is off, provided the distance is great enough.

This is because it has larger surfaces and therefore reflects less scattered signal back.
Serbians exploited that and used NEVA’s 144MHz (~2 m wavelength) radar to find it and shoot it down, back in 1999.

In that particular case, the F-117 flew almost directly over the mobile radar site. As the SAM battery commander stated, it took less than thirty seconds from the time the F-117 was first detected until the SAM-3 made impact. The USAF attacked the same target area three nights in a row at the same time, the fourth night the Serbian AD was prepared. The Serbian figured (correctly) the F-117 approached the target from an area between two fixed radar sites. They positioned a mobile sight directly between the two fixed sights. The AWACS detected the mobile radar site when first started broadcasting, AWACS alerted the F-117 pilot but, he decided to proceed with the mission.
The reality is no other F-117s were shot down, the problem of detecting the F-117 remains.