UK Defence Forum

I think you are mixing g's with velocity. But whatever.

Soft launch is nice but doesn't work for big boy missiles.

[quote="Ron5"]I think you are mixing g's with velocity[/quote

What is G force - to find the meaning of g forces, especially for those who have little or no idea about g forces. Read on.

G-force stands for either the force of gravity on a particular extraterrestrial body or the force of acceleration anywhere, the g-force on an object is its acceleration relative to free-fall. The object experiences this acceleration due to the vector sum of non-gravitational forces acting per unit of the object's mass. These accelerations, also known as "proper accelerations,”

The vector sums at the early part of the launch are simple, as the missile is going in a straight line. Why does it have decrease its acceleration so quickly after the peak has been achieved after one third of a second? In the other two thirds it not only needs to flip, to point in the right direction, but also be rather stable at the point when the rocket motor ignites, at this point being 30 meters higher and practically level (see the video)
- the initial force, and the positional adjustment forces at this point "are spent"
- the much greater thrust force takes over
- this is all common sense (and physics) which one can evidence by the eye... DERA has even measured it
- to me ' and " are not symbols denoting length, but something else (in the maths and physics curriculum at 15)

Ron5 wrote: Soft launch is nice but doesn't work for big boy missiles.

This statement is correct; it is in reference books, too.

Going back to the CAMM-sized missiles that we were discussing, the "overhead" I tiried to refer to "in shorthand" - that has to be incorporated into the missile itself for soft launch - can be translated to a 10% range sacrifice... no free lunches in this world, unfortynately.

ArmChairCivvy wrote:can be translated to a 10% range sacrifice... no free lunches in this world, unfortynately.

But we could fit a 30% larger missile in the same space, since no space in needed for hot exhaust management, so surely that offsets the range effect.

Ron5 wrote:Soft launch is nice but doesn't work for big boy missiles.

True, and with a slight variation similar benefits are possible.....



Cold launched, and ignites away from the ship, dispensing the need for hot gas management, whilst maintaining commonality between ship and sub cruise missiles. I like it.

shark bait wrote:But we could fit a 30% larger missile in the same space, since no space in needed for hot exhaust management, so surely that offsets the range effect.

We could, indeed. Now let me get the calculator out CAMM: 3.2 m[2]
CAMM-ER: 4.0 m[3
And as the booster is all rocket motor+fuel, the range extension is more than the percentage would let one believe
... and also the Spanish navy is at it, with the latter, not just the Italian Airforce

Soft launch is nice but doesn't work for big boy missiles.

Tell it to the russians. They chuck stuff such as S400 out on cold launch, and several ICBMs too, including the Topol M, are ejected cold and ignite outside the laundher...

As standard, along side a manned helicopter, or instead of????

ArmChairCivvy wrote:

Ron5 wrote:I think you are mixing g's with velocity[/quote

What is G force - to find the meaning of g forces, especially for those who have little or no idea about g forces. Read on.

G-force stands for either the force of gravity on a particular extraterrestrial body or the force of acceleration anywhere, the g-force on an object is its acceleration relative to free-fall. The object experiences this acceleration due to the vector sum of non-gravitational forces acting per unit of the object's mass. These accelerations, also known as "proper accelerations,”

The vector sums at the early part of the launch are simple, as the missile is going in a straight line. Why does it have decrease its acceleration so quickly after the peak has been achieved after one third of a second? In the other two thirds it not only needs to flip, to point in the right direction, but also be rather stable at the point when the rocket motor ignites, at this point being 30 meters higher and practically level (see the video)
- the initial force, and the positional adjustment forces at this point "are spent"
- the much greater thrust force takes over
- this is all common sense (and physics) which one can evidence by the eye... DERA has even measured it
- to me ' and " are not symbols denoting length, but something else (in the maths and physics curriculum at 15)

CAMM acceleration stops as soon as the gas piston stops pushing it. Force from the piston starts strong and gets weaker as it transits the cell. Acceleration follows that profile.

ArmChairCivvy wrote:

Ron5 wrote: Soft launch is nice but doesn't work for big boy missiles.

This statement is correct; it is in reference books, too.

Going back to the CAMM-sized missiles that we were discussing, the "overhead" I tiried to refer to "in shorthand" - that has to be incorporated into the missile itself for soft launch - can be translated to a 10% range sacrifice... no free lunches in this world, unfortynately.

The is no range penalty for soft launch. Where are you getting this nonsense from??

ArmChairCivvy wrote:

shark bait wrote:But we could fit a 30% larger missile in the same space, since no space in needed for hot exhaust management, so surely that offsets the range effect.

We could, indeed. Now let me get the calculator out CAMM: 3.2 m[2]
CAMM-ER: 4.0 m[3
And as the booster is all rocket motor+fuel, the range extension is more than the percentage would let one believe
... and also the Spanish navy is at it, with the latter, not just the Italian Airforce

If you guys actually looked at a cross section of a Mk41 vs a CAMM cell, you will see that your math is wildly inaccurate.

Gabriele wrote:

Soft launch is nice but doesn't work for big boy missiles.

Tell it to the russians. They chuck stuff such as S400 out on cold launch, and several ICBMs too, including the Topol M, are ejected cold and ignite outside the laundher...

When I said "work", I implied "work to a western standard for reliability & safety".

SKB wrote:

Jones should look up from his desk, other navies have been doing this as standard ops for some time now. 2023 puts the RN well behind the curve.

P.S. in a related announcement, Leonardo says its developing a UK unmanned helo for the RWUAS project and will be ready for the Type 31 also. Work being done in the UK.

Ron5 wrote:If you guys actually looked at a cross section

Length and cross section can be used together, for some useful comparators to be produced. Like velocity and acceleration are somewhat related (but far from being the same thing).

Jane's is reporting that Chilean Navy is considering buying additional Type 23 frigates after British representatives have said that ships could soon be for sale.

They state that sources have told them that the UK has alerted Chile and Brazil about the potential availability of Type 23 frigates and Albion-class LPDs which could become surplus after the current defence review.

Would this just be a temporary reduction to the 19 FF/DD i.e. selling off the T23 that are currently unmanned but still buying 8 T26 and 5 T31? Or would it be another permanent cut to frigate numbers?

Assume the worst and you'll not get any nasty surprises.

Aethulwulf wrote:Jane's is reporting that Chilean Navy is considering buying additional Type 23 frigates after British representatives have said that ships could soon be for sale.

They state that sources have told them that the UK has alerted Chile and Brazil about the potential availability of Type 23 frigates and Albion-class LPDs which could become surplus after the current defence review.

Would this just be a temporary reduction to the 19 FF/DD i.e. selling off the T23 that are currently unmanned but still buying 8 T26 and 5 T31? Or would it be another permanent cut to frigate numbers?

Short of a cash miracle, there already is a permanent cut to 8 frigates anyway.

RetroSicotte wrote:
Short of a cash miracle, there already is a permanent cut to 8 frigates anyway.

shortage of manpower is exacerbating the problem

so kent is in refit at minute what other ones are and what stages are they at?

marktigger wrote:so kent is in refit at minute what other ones are and what stages are they at?

This is from July so is outdated, but gives you a decent idea what ships have recently been refitted and are in post refit workup.

So I just researched it best I can. That graph seems fairly accurate as far as the current situation goes. This is what I came up with on my own.

Currently:
4x Active (No Sea Ceptor)
3x Post Refit (Sea Ceptor)
3x Undergoing Refit (To receive Sea Ceptor)
2x In Maintenance
1x Laid up

Listed from oldest to newest.

HMS Argyll (GP) - Post Refit (Seaceptor)
HMS Lancaster (GP) - Undergoing refit 2017
HMS Iron Duke (GP) - Active
HMS Monmouth (GP) - Active
HMS Montrose (GP) - Post Refit (Seaceptor)
HMS Westminster - Post Refit (Seaceptor)
HMS Northumberland - Undergoing Refit 2017
HMS Richmond - Active
HMS Somerset - Maintenance
HMS Sutherland - Active
HMS Kent - Undergoing Refit 2017,
HMS Portland - Laid up due to lack of crew
HMS St Albans - Maintenance

Aethulwulf wrote: Or would it be another permanent cut to frigate numbers?

350% this.