Why so many JASSM?

Reaction time and PK are different.

It increases mission success, slightly, for the JASSM/JSOW, since they reduce the time they are “fired” at by the S-300, if that even makes a difference, as during the time given against even stealthy targets, an S-300 battery might run out of missiles. That’s a calculation you clearly have not done.

If you don’t have time to react, then you’re going to have a pretty low probability of a kill.

Stated ranges are typically given using cued search mode, while volume search mode is used 99+% of the time in reality. The range difference between cued search and volume search is on the order of 25-30%. The detection range drops even more if you use 90% probability of detection instead of 50% probability of detection. “Facts” from salesmen’s brochures can be misleading if you are not aware of the groundrules and assumptions behind them.

Ah, but this is not completely true for the S-300/400 systems. The engagement radar (FLAP LID, TOMB STONE, or GRAVE STONE) is cued by the battle management radar (BIG BIRD). While BIG BIRD may be operating in a volume search capacity, the engagement radars are most certainly not. So, if the 400km figure applies to the GRAVE STONE, then it could be treated as accurate, as the system is cued.

Reducing the RCS question to the head-on aspect is like looking into the exhaust of an idling J79 and saying ‘but it’s not noisy at all!’.

Not if you have good situational awareness through ESM, RHAW, RWR, etc.

Reducing the RCS question to the head-on aspect is like looking into the exhaust of an idling J79 and saying ‘but it’s not noisy at all!’.

Isn’t F-35 stated to have RCS the size of a golf ball at front aspect ?

Perhaps… The S-400 radar system is supposed to be able to detect a 1m2 object 400km away. If the RCS of F-35 is 0.001 (and if I did my math right) then the S-400 should be able to detect the F-35 at a distance of 71 km.

But I guess the tracking distance is the more relevant here… And I have no idea what that would be?

The SPY-1D radar is said to be able to track a golf ball sized object at a distance of 165 km!

What’s the RCS of a golf ball ?
L

Stated ranges are typically given using cued search mode, while volume search mode is used 99+% of the time in reality. The range difference between cued search and volume search is on the order of 25-30%. The detection range drops even more if you use 90% probability of detection instead of 50% probability of detection. “Facts” from salesmen’s brochures can be misleading if you are not aware of the groundrules and assumptions behind them.

LOL. Russian sales brochures which claim to have long range anti-stealth capability are talking about their abilities against Gen 4 airplanes like F-15E, F-16C, F-18C/E/F, Rafale and Typhoon which have RAM/conductive coatings and FSS. But those airplanes are not state-of-the-art in stealth which are several orders of magnitude lower in RCS.

Perhaps… The S-400 radar system is supposed to be able to detect a 1m2 object 400km away. If the RCS of F-35 is 0.001 (and if I did my math right) then the S-400 should be able to detect the F-35 at a distance of 71 km.

But I guess the tracking distance is the more relevant here… And I have no idea what that would be?

The SPY-1D radar is said to be able to track a golf ball sized object at a distance of 165 km!

http://sill-www.army.mil/famag/2004/MAR_JUN_2004/PAGE24-25.pdf

While the SPY-1D has been designed primarily to detect theater ballistic missiles (TBMs) at ranges in excess of 500 kilometers, it also can track golf ball-sized targets at ranges in excess of 165 kilometers.

What’s the RCS of a golf ball ?

L

LOL. Russian sales brochures which claim to have long range anti-stealth capability are talking about their abilities against Gen 4 airplanes like F-15E, F-16C, F-18C/E/F, Rafale and Typhoon which have RAM/conductive coatings and FSS. But those airplanes are not state-of-the-art in stealth which are several orders of magnitude lower in RCS.

I think the HPM warhead will play a big role in the future, making everything that isn’t hardened or at least shielded close to worthless. And one can only imagine what a salvo of HPMs does to a SAM site’s electronic.

I’m convinced ultra-high-speed ARM volleys is the right way to go to silence SAM-sites, preferably with some loitering backups like Alarm or the purpose-built Israeli UAV.

The F 35 will have a long range, high-precision, stealthy weapon: the Joint Strike Missile (JSM) based on Norvegian NSM (Naval Strike Missile). It’s a mini-cruise missile, it will offer a ~ 100 Nmiles range, and will be able to attack double digit SAMs.

OTOH, the JASSM will be used be heavy bombers (B1, B2, B 52) and non-stealthy F 18 E and F 16.

Yes, I am familiar with the JSM 🙂 Unlike the JASSM, the USAF has not (yet) ordered a single JSM, hopefully they will. The JSM will actually have a range of “more than 150 nm”, whereas the NSM has a range of “more than 100 nm”. Apart from the range one important difference between JASSM and JSM is the size of the warhead. The JASSM can attack hardened targets whereas the JSM is less suitable for such operations.

THe JASSM will also be integrated on the F-35, so I assume it will be used. The F16 will be phased out. USAF does not fly F18E, that’s the Navy guys.

Anyway my original question was not “why are they buying JASSM” but rather “why are they buying so many JASSM” given that in a few years most USAF missions will be done by the stealthy F-35 that can operate much cheaper stuff than JASSM. Also, with the stand-off range of JASSM you simply don’t need the F-35 to launch it.

I have done some digging and found that in conjunction with the Iran/Israel situation and the possibility of Iran obtaining S-300, it seems that LM has stated that F-35 can “defeat S-300 in combat”.

http://www.upi.com/Security_Industry/2009/01/20/Can-the-US-F-35-fighter-destroy-Russias-S-300-systems/UPI-39001232464740/

Interestingly I have not found much claims that S-300 system will be able to “handle” VLO targets. OTOH there are several claims that S-400 can handle stealth targets;

http://www.missilethreat.com/missiledefensesystems/id.52/system_detail.asp

The S-400 system can intercept and destroy airborne targets, including stealth aircraft, cruise missiles and ballistic missiles…

and I have not found any claims from LM that F-35 can defeat the S-400. Presumably the S-400 will be a much tougher nut to crack for the F-35 than the older S-300 systems.

L

According to DefenceUpdate USAF plans to purchase 4900 JASSM and JASSM ER.

http://defense-update.com/products/j/jassm.htm

AFAIK the JASSM cannot be carried internally in the F-35; it will be carried externally and make the F-35 dirty.

Since USAF is going for a massive switch to the F-35 for the coming years I was wondering about the logic behind this? Why purchase so many JASSMs when they will soon be flying F-35s that can use e.g. the JDAM which is much cheaper and can be stored internally, and thereby maintaining the low RCS of the F-35.

The long range of the JASSM means that one does not need the low RCS of a clean F-35, but then again you don’t need the F-35 at all.

Some speculations: Could it be that the F-35 with it’s “golf-ball” RCS could face problems when entering, say, an area protected by S-400/S-500, and therefore one still needs some heavy standoff weapons?

L

The F 35 will have a long range, high-precision, stealthy weapon: the Joint Strike Missile (JSM) based on Norvegian NSM (Naval Strike Missile). It’s a mini-cruise missile, it will offer a ~ 100 Nmiles range, and will be able to attack double digit SAMs.

OTOH, the JASSM will be used be heavy bombers (B1, B2, B 52) and non-stealthy F 18 E and F 16.

In how many directions can a SAM battery shoot simultaneously? Remember, the PGMPS (Precision Guided Munitions Planning System) plans JASSM, JDAM and SDB routes in four dimensions, the 4th dimension being time. And if the shooter is an F-35, it will be also conducting and electronic attack against your TTR and missile datalinks during those last critical seconds. The EA doesn’t have to negate the TTR or datalinks, just slow them down enough (as they switch ECCM modes) so the PGMs get through.

F-35 is capable of employing JDAMs or LGBs against less capable double digit SAMs such as Tor-M1, Buk-M1, Pantsyr, ZRK-BD (less radar power = shorter detection ranges against stealthy targets). But Gripen doesn’t have enough stealth to keep those same SAMs from shooting it before it can drop bombs using a medium altitude attack. This forces Gripen to use terrain masking and causes a dramatic reduction in Pk against the SAM battery, meaning more Gripen sorties would be required for DEAD.

Against a TOR, the bombs themselves may get shot down.

In the other cases, I don’t see a competent SAM commander emitting blindly or standing in the open for the F-35 to fly in and bomb the SAM battery. Best tactic would be to wait for the F-35 to be right over you, then pop out of cover, fire, and move.

On a side note, another reason for all those JASSMs is the mighty TOR was shown engaging 4 targets within 10 seconds at MAKS!

🙂

The S-300 may be able to engage 6 targets simultaneously, but the thing to take into consideration is that the JASSM/JSOW have low RCS, which means the amount of reaction time will be limited, lowering the PK.

Reaction time and PK are different.

It increases mission success, slightly, for the JASSM/JSOW, since they reduce the time they are “fired” at by the S-300, if that even makes a difference, as during the time given against even stealthy targets, an S-300 battery might run out of missiles. That’s a calculation you clearly have not done.

You’ll need a lot more than two. One S-300PM battery can engage six targets at once, so you’ll need at least seven missiles to saturate it. That is assuming that missile 7 hits the site before any of missiles 1-6 are shot down, allowing missile 7 to be engaged.

Except that none of those radars are used by the S-300V (SA-12)…it uses BILL BOARD for TA, GRILL PAN for TT, and HIGH SCREEN for TBM sector scanning.

The S-300 may be able to engage 6 targets simultaneously, but the thing to take into consideration is that the JASSM/JSOW have low RCS, which means the amount of reaction time will be limited, lowering the PK.

I’ve only read that those might be a future development, is anyone actually working on such a missile?:confused:

Yes, Boeing and Raytheon. Google “Joint Dual Role Air Dominance Missile”

You read right, but IMV it is just too good idea to pass on.

I think a volley of Meteor-derived ARM’s would be really tough to intercept in time.

I’ve only read that those might be a future development, is anyone actually working on such a missile?:confused:

I think a volley of Meteor-derived ARM’s would be really tough to intercept in time.