A ratio needs the numbers that were on both sides to be relevant.

ATK was awarded a contract to develop new technologies for a new motor for the AMRAAM in 2009. They are due to complete it in 2013. One aspect (out of 4) is for new propellants. Keep in mind they never has a problem with the original AMRAAM motor but only with the new formula mandated by tree-hungers.

The scope of the CA/FNC program is to develop technologies that will extend missile range, decrease time-to-target, improve end-game maneuverability, and improve the rocket motor’s response to insensitive munitions (IM) stimuli. These improvements are oriented towards the 7-inch diameter Advanced Medium Range Air-to-Air Missile (AMRAAM) that is currently in use by the U.S. Navy, U.S. Air Force, and many allied nations, but will be applicable to other air-to-air missile systems.

There are four main areas that ATK will be concentrating their development efforts on which include: high burn rate propellants for improved kinematics; improving case stiffness for reduced weight and agility; low erosion nozzles for improved performance; and multi-pulse propulsion for end-game maneuverability. Additionally, ATK will address the IM requirement by incorporating affordable solutions including an advanced propellant formulation, a low cost composite case, and mitigation safety devices proven on other tactical rocket motor programs.

As far as thrusters being too much of a risk, they have extensive experience with them in PAC-3.

Are you sure?

I count the forward thrusters (I’m pretty set at this point as to their use) as part of the motor in my calculation of the ratio. The reason is that the thrusters allow for much smaller control surfaces to be used thereby reducing drag and allowing the motor energy to be more efficiently used.

Sorry for the confusion.

Aka less jamming resistant.

If it uses a band that is not normally covered in a jammer (aka MMW) then it would be jam resistant. If LM was smart they would recycle their JAGM MMW seeker work.

For that matter, how many ESM sets even cover MMW?

—Updated ratios

I pulled these motor number directly from ATK and they include the blast tube (links below). I pulled the overall length from Raytheon (links below) and it’s in inches.

Missile Length Motor Ratio Ratio with Thruster Section<br />
AMRAAM 144 74.4 51.67%<br />
9x 119 78 65.55%<br />
CUDA 70.8 46.25 65.32% 82.27%<br />


9x info:
http://www.raytheon.com/capabilities/products/stellent/groups/public/documents/content/cms01_054518.pdf
http://www.atk.com/wp-content/uploads/2012/09/MP-Sidewinder-AIM-9X-Propulsion.pdf

AMRAAM info:
http://www.designation-systems.net/dusrm/m-120.html
http://www.atk.com/wp-content/uploads/2012/09/MP-AMRAAM-Propulsion.pdf

Even without counting the 12 inch mystery section as part of the motor, the CUDA beats the AMRAAM ratio and ties the 9x.

Takeaway: Motor ratio is not the only determining factor in range as the 9x does not come close to the AMRAAM’s range despite having a larger motor (in percentage and actual length).

Things to keep in mind:

1. It’s at least 8-10 years from IOC (if it happens) and a lot can happen in materials tech before then.
2. Propellants are always being improved. ATK is currently working on a new motor for AMRAAM with this in mind.
3. Space is not needed for a proximity fuze
4. Space is not needed for a large (if any) warhead
5. The seeker does not have to be powerful (therefore will be smaller) since WVR is the target range.
6. The battery does not have to be as large as AMRAAM due to no proximity fuze, a much shorter flight time, a smaller seeker, and improvements in battery tech.

Given all of that, it is safe to say that the CUDA will have a much larger missile:motor ratio than AMRAAM or even Sidewinder.

CUDA should be at least Aim-9 range which is much better than gun range.

Profit by meeting the requirement, then profit some more by improving on a potential requirement shortfall. Brilliant. :p

Fixed it for ya 😉

An uncharitable person might point out that while LM has never designed an AAM, they have designed and fielded a HTK SAM (PAC-3) that goes after targets that are much faster and smaller than a fighter. 😉

To put in the simplest terms, liquid fuels have better specific impulse (less fuel required per pound of thrust), can be throttled, and can be stopped & started. Problem is they leak due to high corrosion issues. They also have the tendency to go bang at the wrong time.

Solid fuel motors are safe for long term storage but cannot be throttled or restarted.

Gel Fuels try to get the best of both worlds, high impulse and throttle-ability of a liquid and safe storage of a solid.

Spud, are those ext pylons the same as the ones used on F-16, or are they new developed only for F-35?
It may just be imagination, but those pylon look huge on the F-35 pic..

New for the F-35.

please pay attention to facts. Block 2 has no external weapons capability. Nor does Block 3I. So far, publicly, Block 3F does, but it has no firm IOC date for the US, so I do not know how it can be part of a firm-price offer to Korea. If the Korean initial delivery standard is 3I, then external weapons will be an extra to be added later.

The pylons are already flying and if external carriage is required for Korea and is needed for 3I then LM/JPO can spend some extra money and make it happen. We are talking about 3-4 years from now so there is time if needed.