DARPA Long Range Anti-ship Missile (LRASM)

[Jimmo952]

I did not know that the LRASM used the Harpoon warhead? That is news to me, I wonder what made them go down that route? Money?

Hmmmm. The original LRASM used the JASSM warhead.

Variants were proposed that sacrificed warhead size for range, but this is the first I've heard the Harpoon warhead actually being used.

 

[Forest Green]

I did not know that the LRASM used the Harpoon warhead? That is news to me, I wonder what made them go down that route? Money?

My guess would be range. The extra electronics weigh more, so they reduced warhead size to 500lb (unless they went with the 800lb warhead from the SLAM-ER) to claw back the range. The JASSM warhead weighed 1000lb but only contained 240lbs of AFX-757.

 

[TomS]

Hmmmm. The original LRASM used the JASSM warhead.

Variants were proposed that sacrificed warhead size for range, but this is the first I've heard the Harpoon warhead actually being used.

It's speculation by Josh_TN.

 

[Josh_TN]

I did not know that the LRASM used the Harpoon warhead? That is news to me, I wonder what made them go down that route? Money?

It uses the standard JASSM warhead. I am speculating that the warhead was changed on the new extended range version but that is purely a guess.

 

[Forest Green]

LRASM test proves missile's superior capabilities in navy flight exercise

Los Angeles CA (SPX) Apr 08, 2024 - In a significant advancement for maritime defense, the U.S. Navy and Lockheed Martin [NYSE: LMT] have successfully completed a critical flight

www.spacewar.com

 

[NMaude]

In regards to the Mk-114 rocket-motor for launching the LRASM from the Mk-41 VLS does anyone know its' length and weight? The only figures I know are its' diameter (14.1"), Thrust (11,000Lb) and burn time (5s).

 

[Josh_TN]

In regards to the Mk-114 rocket-motor for launching the LRASM from the Mk-41 VLS does anyone know its' length and weight? The only figures I know are its' diameter (14.1"), Thrust (11,000Lb) and burn time (5s).

I do not know the figures you are looking for, but I am confident the USN will never adopt LRASM as a surface launched weapon. So it probably is not super relevant.

 

[Forest Green]

I do not know the figures you are looking for, but I am confident the USN will never adopt LRASM as a surface launched weapon. So it probably is not super relevant.

What was the reason for that anyway? Because they had Tomahawk already?

 

[Josh_TN]

What was the reason for that anyway? Because they had Tomahawk already?

That and the fact JASSM/LRASM seem to operate from medium altitude, so boosting from the surface and using the turbofan to climb will burn through range of an already shorter ranged missile. SM-6 can already out range AGM-158C-1 from a surface launch. LRASM does not fill a capability niche not already filled by other types.

 

[Scott Kenny]

In regards to the Mk-114 rocket-motor for launching the LRASM from the Mk-41 VLS does anyone know its' length and weight? The only figures I know are its' diameter (14.1"), Thrust (11,000Lb) and burn time (5s).

Given thrust and burn time, I would expect it to be similar in length/weight to the booster of the Harpoon.

 

[NMaude]

Given thrust and burn time, I would expect it to be similar in length/weight to the booster of the Harpoon.

A quick look at the Mk-114 shows that it's about twice the length of the Harpoon's launch booster and is about two-thirds the length of a Mk-46 torpedo, now that I think about it after seeing some images I wouldn't be surprised at all if the Mk-114 is the same length as the RUR-5 ASROC's Mk-37 launch booster.

 

[Scott Kenny]

A click look at the Mk-114 shows that it's about twice the length of the Harpoon's launch booster and is about two-thirds the length of a Mk-46 torpedo, now that I think about it after seeing some images I wouldn't be surprised at all if the Mk-114 is the same length as the RUR-5 ASROC's Mk-37 launch booster.

Should be pretty close, the Mk46 torpedo from ASROC is 2.59m and the Mk54 torpedo is 2.72m. Any interstage is going to be about the same length due to the very similar shapes of the back ends of the torpedoes.

 

[NMaude]

Any interstage is going to be about the same length due to the very similar shapes of the back ends of the torpedoes.

Don't forget that attached to the torpedo's back end is the Mk-28 torpedo stabiliser (A retarder parachute) and sandwiched between that and the Mk-114 booster is the INS and Mk 210 Mod 0 Digital Autopilot Control subsystem.