Altitude. The wings are designed to deploy almost immediately. And the drag of the wings cause the munition to decelerate quickly until the optimal glide speed is reached.

SPEAR range should be much less altitude dependence compared to SDB

ANALYSIS: F-35’s next engine to reach for more range
06 Aug 2019 Garrett Reim

“One criticism – among many – of the Lockheed Martin F-35 Lightning II is that the fighter lacks the range needed to conduct long-range stealth strike missions. While Lockheed Martin has studied adding external fuel tanks to extend the aircraft’s range, slinging the bulky hardware under the F-35 would ruin its minimal radar cross section, giving away the stealth fighter’s chief advantage.

In place of extra onboard fuel, the US Navy (USN) has boosted the flight endurance of its F-35C variant by using its Boeing F/A-18E/F Super Hornet as a substitute in-flight refuelling tanker. The service is also funding the development of four Boeing MQ-25A Stingray unmanned in-flight refuelling tankers for $805 million….

…The USAF is looking at how the F-35 can do more with its fuel capacity. One important effort is the service’s Adaptive Engine Transition Program, which aims to create a novel engine that has not only more power, but also more fuel economy.

Adaptive engines work by varying the volume of air flow that bypasses the turbine core by opening a third stream when flying in cruise mode. This third flow – in addition to core flow and bypass flow – increases the engine’s efficiency in producing thrust and also creates a new heat sink within the engine, allowing for further fuel efficiency gains from increased core temperature. The result is an engine that can play the turbofan’s efficiency trick of running a large bypass ratio when cruising – while retaining the raw power of a turbojet in other situations….

...For its part, GE Aviation announced the successful completion of the XA100 detailed design process in February 2019. The company believes the engine could result in a 35% increase in range and a 50% improvement in loiter time. That range improvement applied to the F-35C would add 420nm – taking range for the USN’s variant to 1,620nm.

“In the Pacific theatre of operations this is significant, allowing either operations from greater distances or more time to operate at the combat edge,” says USAF Major General Larry Stutzriem (retired), now director of research with the Mitchell Institute for Aerospace Studies. “This improvement could also allow F-35s to drop from their tanker support earlier, keeping those extremely vulnerable aircraft further away from adversary defences.”…”

https://www.flightglobal.com/news/articles/analysis-f-35s-next-engine-to-reach-for-more-range-459856/

3) Current stealth technology tends to break down at lower frequencies.
This is true. The canopy effect is one reason for this. The wavefront passes through the absorber/coating materials more easily and then non-stealthy shapes such as the instrumentation and the pilot’s helmet start contributing to RCS. There is also the more widely known case of Mie scattering. The Su-57 – with its many thin, transparent surfaces – will have a very pronounced canopy effect. This is why they had to build Okhotnik. The Su-57 isn’t as suited for deep penetration tasks as the F-35 or J-20 is because it is particularly vulnerable to detection at low frequencies.

I want to add that low RCS at VHF is a requirement of F-35
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Block 4 upgrade

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I hope my comment pass the moderation.

I am sure it will, your knowledge of military equipment is head and shoulder above any other enthusiasts that i have chance to talk to.

support hjammig is 70ies techniques (à la Growler). You did not answer about the age of your antique book. J/S ration is just good for white noise jamming, aka granddaddy’s.

That is completely wrong
Support jamming aka: EA-18G, NGJ, MALD-J, MALD-X, SPEAR-EW all uses noise jamming.
Deceptive jamming such as RGPO, RGPI, VGPO ..etc can’t be used to support others assets other than the one carry the jammer.
So your dissing of noise jammer is the same as someone who dissing jet engine or radar because their working principles are well understood.
The book was published in 2004 by real expert, frankly make it better than 99.9999% of common tabloids such as Defenseaerospace and Sputnik
FYI, J/S is not only important for noise jamming
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https://books.google.com.vn/books?id…page&q&f=false
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https://books.google.com.vn/books?id…page&q&f=false (this book was written in 2015)

is not operational, first release from B21 being a year old. Aka It is efficient as Nothing. Dosent even have EOC on F-18, not to say F-35… Short legged interim solution, real competition will be in 2024.

Don’t try to divert attention from what you said earlier
You said LRASM is too slow so the only hope to penetrate air defense is by number, yet Storm shadow at best case scenario is 50-100 km/h faster.
You said JSM is short range, yet it is only 10 km shorter range than Storm shadow.
and for your information:

On November 12, 2013, an LRASM scored a direct hit on a moving naval target on its second flight test. A B-1B bomber launched the missile, which navigated using planned waypoints that it received in-flight before transitioning to autonomous guidance. It used onboard sensors to select the target, descend in altitude, and successfully impact.^[35][36] On 4 February 2015, the LRASM conducted its third successful flight test, conducted to evaluate low-altitude performance and obstacle avoidance. Dropped from a B-1B, the missile navigated a series of planned waypoints, then detected, tracked, and avoided an object deliberately placed in the flight pattern in the final portion of the flight to demonstrate obstacle-avoidance algorithms.
On 4 April 2017, Lockheed announced the first successful release of the LRASM from an F/A-18 Super Hornet.^[43] On 26 July 2017, Lockheed was awarded the first production award for the air-launched LRASM; low-rate initial production Lot 1 includes 23 missiles.^[44] On 27 July 2017, Lockheed announced they had successfully conducted the first launch of an LRASM from an angled topside canister using a Mk-114 booster, demonstrating the missile’s ability to be utilized on platforms lacking vertical launch cells.^[45]
In December 2018, the LRASM was integrated on board the USAF’s B-1B bomber, reaching Initial operational capability; the missile is scheduled to achieve IOC on the U.S. Navy’s F/A-18E/F Super Hornet in 2019.

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(i) i prfer numbers to bold affirmations like “in every bit)
(ii) not operational yet so if you want o compare, compare to NGM or to perseus

LRASM is JASSM-ER airframe with different sensor: crusing speed is Mach 0.85
JSM speed is Mach 0.95
Storm shadow speed range from Mach 0.8-0.95
AARGM-ER speed is Mach 3
HAWC speed is > Mach 5
in best case scenario, Stormshadow is barely 100 km/h faster than LRASM