External Load RCS is it that bad? Why?

[gambit]

I think such 'coverings' also known as cocoons will deploy spring mounted pneumatic legs for missiles (such were also employes in TU-95 & MiG-31 for R-33/37 missile) to push the missile away from the fuselage & then turn on rocket moor; such technique will hardly interfere with missile shapes & isn't complex; also semi-recessed missile bays also reduce RCS

Whatever mechanisms employ, there is still the need for that %99.999 reliability. The simplest offer the greatest odds to achieve that goal.

 

[SnakeBoat]

Gambit,
Thanks for the educational discussion on RCS.
From what I understand,
1) The airframe + necessary structures for aerodynamics should have designs that reduce RCS.
2) Weapons have to be designed for each aircraft type to conform to reduction of RCS, so as to not pose an interactive signature that exceeds nominal acceptable values.
As someone suggested in the thread, if the aircraft is designed in a way with recessed bays (or whatchamicallit "cubbyholes") for missiles and large ordinances, and if the weapons/ordinances themselves are packaged with say "a honeycomb" like outerstructure that falls off say fractionally before the missile or bomb itself is released and fired, would that be good?

 

[gambit]

Gambit,
Thanks for the educational discussion on RCS.

Yer welcome.

From what I understand,
1) The airframe + necessary structures for aerodynamics should have designs that reduce RCS.

From scratch, yes.

2) Weapons have to be designed for each aircraft type to conform to reduction of RCS, so as to not pose an interactive signature that exceeds nominal acceptable values.

Ideally, yes. Those 'nominally acceptable values' are grouped in what is called 'clutter rejection threshold'. What we call 'clutter' is merely what we rejected from detection, not necessary what we detected in the first place. In other words, we can detect everything down to cosmic background radiation (CBR). But is that what the military want? No. So we filter out CBR, birds, meteorological phenomenon, ground EM sources, and many more. What is 'clutter' or rejected garbage to one person is treasure to another. For the military, raindrops are junk but to the meteorologist it is the aircraft that is junk. The goal of 'stealth' is to insert the aircraft and whatever that it may carry into that rejection threshold.

As someone suggested in the thread, if the aircraft is designed in a way with recessed bays (or whatchamicallit "cubbyholes") for missiles and large ordinances, and if the weapons/ordinances themselves are packaged with say "a honeycomb" like outerstructure that falls off say fractionally before the missile or bomb itself is released and fired, would that be good?

The idea is not new and its history has more to do with aerodynamic drag than it is with RCS control. But now it is different.

 

[AZADPAKISTAN2009]

For sake of simplicity lets just build planes with internal weapon's bay - end of story

 

[SQ8]

Any external pod will have its own extra weight, such as the one for the SH in its roadmap.
The best solution is always internal, but.. question is.. if it is a sum game of RCS's..
then if one is able to keep the RCS of a platform itself comparatively low.. and then make the thing sit in an anechoic chamber with external loads to see where best to get destructive interference.

 

[SpArK]

Solution

External weapons pod.

 

[Tempest II]

Thank you all for contributing to the discussion.

I see the weapons in a stealthy pod as what the Russians have done with the T-50 and its SRAAMs.

Internal bays have space restrictions.

Why is the F-22 flying with external tanks not optimized for stealth? f-22 external fuel tanks - Google Search

 

[Chogy]

When external stores are hung, huge areas of return form between the aircraft, pylon, and store. In particular, almost all aircraft external stores have "fins" of some type, and by placing a fin right next to an aircraft, even that small area creates a 90-degree reflected bounce. This also occurs on the fins of the missile or bomb itself.

In very simple layman terms, if an area "appears" busy, with lots of small metallic objects in proximity, it tends to create a return. Think of an engine exhaust or intake unprotected, or a cluster of AA missile fins on a pylon.

One of the largest returns comes from a traditional cockpit. In older airplanes, the radar signal enters, bounces around thousands of times, and exits like a flashlight. And unprotected radomes do this as well, as the signal goes through the RF transparent radome and pops right out. Technologies to limit these are very classified. That cool tinted canopy on the newer F-16's isn't a giant ray-ban sun screen!

Even tiny corner reflectors make a powerful signal. For aerial gunnery training, a plywood target is put together, and so it can be seen on radar, a single aluminum sheet corner reflector is bolted on the back. This device is only 1/2 a meter across, yet can be locked up like a B-52.

Again, in simple terms, if it looks busy, jumbled, and it's metallic, then it'll be reflective.

The fins on this AIM-9 alone could be seen at great distances by modern radar.

 

[gambit]

Thank you all for contributing to the discussion.

I see the weapons in a stealthy pod as what the Russians have done with the T-50 and its SRAAMs.

Internal bays have space restrictions.

That is the problem for the aero-guys. We radar geeks just provide the data that regularly pisses them off.

Why is the F-22 flying with external tanks not optimized for stealth? f-22 external fuel tanks - Google Search

The F-22 can carry external stores, as in bombs, when the need for low radar observability is either drastically reduced or no longer needed. When an F-22 is in a 'ferry' flight, no need to make life difficult for the air controllers, so external fuel tanks can be used.

 

[kingdurgaking]

That is the problem for the aero-guys. We radar geeks just provide the data that regularly pisses them off.

The F-22 can carry external stores, as in bombs, when the need for low radar observability is either drastically reduced or no longer needed. When an F-22 is in a 'ferry' flight, no need to make life difficult for the air controllers, so external fuel tanks can be used.

Let these logic be eaten by some people here around..

 

[Curious_Guy]

Nice discussion ...Thank you

 

[C130]

so let's say a clean F-16 RCS is 1m2, and fully loaded with external fuel tanks, weapons, it would come out to around 3 to 5m2???

but then let's say the F/A 18 ASH with it's enhanced RCS reduction is .5m2 and using enclosed weapons pods it comes out 1m2?? that'a big difference