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Senate The Weekly Discussion of Military Technology

Discussion in 'Community' started by Mr44, Nov 27, 2003.

  1. Kimball_Kinnison

    Kimball_Kinnison Jedi Grand Master star 6

    Registered:
    Oct 28, 2001
    That's not actually a very big concern.

    Communications satellites are placed in geostationary orbit, which has two important constraints. First, they have an altitude of about 22,236 miles. Second, they can only be placed in the Earth's plane of rotation (which means that they have to be directly above the Equator).

    The Earth's atmosphere goes about 62 miles straight up, at which point you are considered to be in space (although the atmosphere really continues past that limit, but in a much thinner form). That means that a laser fired would have to travel at least 62 miles through the atmosphere, and likely much more (depending on the angle it's fired at). As it moves through the atmosphere, it will lose significant amounts of energy. Additionally, because lasers aren't perfectly straight (they actually spread out at an angle, or diffuse), the width of the beam would continue to expand over the distance to reach a communications satellite. A 1 degree diffusion straight up would cause the beam to be 388 miles wide by the time it reached geosynchronous orbit. That means that the remaining energy would be spread out over an area of over 118000 square miles. Such a short pulse wouldn't do much of anything to a satellite at that range.
     
  2. DarthBoba

    DarthBoba Manager Emeritus star 9 VIP - Former Mod/RSA

    Registered:
    Jun 29, 2000
    In less transformational news, Bell has put a tilt-rotor into the Joint Medium Rotor competition:

    Linkie

    The main point of interest is that the entire engine doesn't move, unlike on the V-22; just the propeller cap and rotor blades, as shown in this illustration:

    [​IMG]

    One would imagine that with all the experience garnered from the XV-15 and V-22 programs, Bell would be pretty good at building these now :p
     
  3. VadersLaMent

    VadersLaMent Chosen One star 10

    Registered:
    Apr 3, 2002
    I was just gonna post about the ship mounted laser. Here it is being tested and you get the view of a drone being hit, and a view from the drone when it's hit:



    Now we just need to miniaturize this so when we have drones over our own skies spying on us we can shoot them down too not to mention how I can use this to clear up traffic.
     
  4. Mr44

    Mr44 VIP star 6 VIP - Former Mod/RSA

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    May 21, 2002
    Ugh. I guess one can't argue with the rationale behind the project. The Osprey is certainly an example of what not to do for something like this:

    1)Unlike the Osprey, only the V-280’s rotors pivot up and down to allow vertical flight. This makes the aircraft more stable in hover mode and gives it better controllability than its predecessor
    2)It is also self-deployable, unlike the Osprey, which must be shipped or flown aboard another aircraft when deployed overseas.

    I like the S-97 Raider concept as outlined in the article much, much, much more.

    One would imagine that with all the experience garnered from the XV-15 and V-22 programs, Bell would be pretty good at building these now :p

    One would think that since the XV-15 concept was unveiled some 35+ years ago, the Osprey would be pretty good, but alas. I guess Bell has to wade through the bad to get to the good?
     
  5. DarthBoba

    DarthBoba Manager Emeritus star 9 VIP - Former Mod/RSA

    Registered:
    Jun 29, 2000
    Well, to be fair-the V-22 was a whole lot more ambitious than the XV-15 ever was. It's bigger, and that always throws a wrench in the works; plus when you discount helicopters, transitioning from vertical to horizontal flight has always been a tricky one-remember how much of a death trap the early models of Harrier were? It eventually got better, but non-helicopter examples of VTOL are always going to be a pain I think.
     
  6. Mr44

    Mr44 VIP star 6 VIP - Former Mod/RSA

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    May 21, 2002
    True...true. I think the overall problems with jet VTOL or tilt-rotor, no matter jet or helicopter is that they don't excel at anything, because their very design is a system of compromises. The Harrier worked for the British because after WWII, the Brits transitioned from full sized carriers (and the then upcoming Super carriers) to smaller "pocket carriers" to save money. But for example, during the Falklands conflict, it's always been said that more Royal Navy Sea Harriers were lost to accidents than were shot down by the Argentinians. I don't know if that's more of a comment on the lack of ability of the Argentinian air force or a example of just how difficult Harriers are to fly, especially in the non-controlled realm of combat. I'd say the majority of the reason that the US Marines went with the Harrier themselves was more out of trying to stand out/ be different so they didn't get their air wing taken over by the Navy, than for any actual performance benefits. The Harrier was simply outclassed by anything in the air, which is why it was always detailed out to static defense roles and ground support missions. These have their place, but not at the inflated price. I can't think of any conflict were the Harrier-either RAF or US Marine- was ever actually used in it's envisioned VTOL role were it mattered- such as taking over destroyed forward air strips by force or using things like parking lots to land on, because the Harrier is simply too vulnerable when it operates in this role. The v2 Harrier kept it serviceable for probably a decade after it should have been retired, but still. I think everyone who used Harriers have now phased them out.

    Harriers seemed to be the jet version of the bullpup small arms fad of the 80's. A handful of nations rushed to jump on the bullpup bandwagon back then because they were "futuristic," but the cost, over-complexity, and limitations meant that almost all of those same nations switched back (or are in the process of switching) to a conventional rifle layout and simply perfecting it.

    The Osprey is the same situation. The Marines spent hundreds of millions of dollars on a "unique" vehicle which doesn't really excel in any area of its expeditionary role. IIRC, I think you previously mentioned that you actually either rode in one, or saw one in use, and characterized it as not being that bad....but not being that bad isn't a good justification for its cost. Such craft seem to be like that scene from Pulp Fiction were Mia Wallace gets a super-expensive milkshake and Vince Vega asks if it's still just milk and ice cream. It looks like the tilt-rotor craft in your link is a further refinement of the concept, so it might start being worth it, but until then, it's still a $5.00 shake.
     
  7. DarthBoba

    DarthBoba Manager Emeritus star 9 VIP - Former Mod/RSA

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    Jun 29, 2000
    Well, to be fair to the Harrier-the rationale for VSTOL/STOL aircraft during the cold war was nuclear destruction of conventional airfields, or severely damaged ones by conventional weapons (given what the Coalition did to Iraqi airfields during the gulf war, not an entirely unreasonable notion, obviously). The British in particular made a big deal out of this; if you read military aviation books from Janes/etc written in that time frame each and every one of them mentions the potential for conventional airfields being destroyed, which given just how much the Soviets invested in short-range nuclear arms isn't wholly unreasonable, I think. It's obviously not such a concern now, but Harriers are still pretty terrifically versatile-we had a squadron's worth on Khandahar Airfield when I was there; pretty sure they were about the only aircraft besides C-130s that could have landed there.

    I've seen Ospreys a few times-buzzing around near my mom's house of all places (she lives not terrifically far from Holloman AFB) and a couple times in Iraq. Can't really comment on flight characteristics as I haven't been in one.
     
  8. Mr44

    Mr44 VIP star 6 VIP - Former Mod/RSA

    Registered:
    May 21, 2002
    Yeah, that's what I mean though. They just don't do anything in relation to their own complexity/relatively high price tag.

    You summarized the Harrier's rationale back then, but even had a a massive WWIII style land war broken out in Europe, I don't think the Harriers would have been used in their theoretical role. Reality dictates that helicopters are vulnerable while hovering. But at least helos can still maneuver. Harriers cost 25 million+ a piece and can't move while they are transitioning between modes. Imagine if just a single cold war ZSU-23mm quad vehicle came upon a group of Harriers that were in the middle of landing on a bombed parking lot in East Germany somewhere "because they could." That Soviet ZSU gunner would have better odds hitting Harriers than if he was at a fun house shooting gallery. Beyond the cold war into GWOT, imagine a platoon of untrained belligerents armed with $500 dollar RPG-7's taking down an entire squadron of Harriers. It would be Mogadishu x1000. Sure, you could utilize security elements to make it safe for the Harriers to be used in that fashion, but that's doctrinally-backwards and resource draining. The limitations of the design meant that Harriers never used their VTOL as intended, and then the only thing left becomes a case of "yeah, it's nice to have..maybe..." It's not a stellar endorsement for the technology vs what is costs to have it.

    I suppose your last example of using Harriers in an "on-scene," rapid reaction, support role kind of justifies it, but just barely. Again. helicopters could probably do 85% of the same job for a 1/10th of the price. Or Air Force A-10's, even if they are stationed at a more secure base 30 miles behind. I'd bet though that there is no way the forward deployed Harriers would ever immediately take off VTOL-style in the middle of a firefight. The last thing anyone would want is to have a Harrier stuck hovering and helpless for 8 seconds trying to get airborne while mortar shells are landing, so even if its counter-intuitive, other jets would actually be more adaptable. Maybe Harrier pilots have guts of steel, but I'd bet there is a Marine policy to either get Harriers off the ground before an anticipated attack and then loiter over the battlefield, or wait until there is a lull, which is really no different than how any other jet is used.

    The Osprey is even worse. And the Ospey costs a jaw-dropping 70 million dollars each, which is 3x the price of the Marine's Super Stallion*, which is a helo perfect for the expeditionary role. Let's see, 3 Super Stallions for the price of a single Osprey, even if the Osprey is able to travel 400 miles further on a tank of fuel. I mean, even the Marine's version of the Chinook/Sea Knight helicopter only has a top speed that is about 30mph less than the Osprey, and the Sea Knight is about 10x less in price and more adaptable. I just can't see where the additional costs of tilt-rotor/VTOL actually make it worth it beyond the theoretical and into the real world at this point in time.

    *=I think the Marines are currently looking at a kind of "super-super Stallion," which costs something like 90-100 million dollars, but I don't think it has moved beyond the prototype stage, and it definitely represents the crazy cost for what you get as well. (at least I hope it hasn't moved beyond the prototype) This version of the Stallion is not what I'm referring to.
     
  9. DarthBoba

    DarthBoba Manager Emeritus star 9 VIP - Former Mod/RSA

    Registered:
    Jun 29, 2000
    Yeah, the CH-53K is taking its time in gestation. Not sure what the exact problem is, but it's not supposed to hit service until 2018 iirc.
     
  10. Mr44

    Mr44 VIP star 6 VIP - Former Mod/RSA

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    May 21, 2002
    Yeah, the "K" model is it. I wasn't quite sure off the top of my head what letter they were up to on that craft.

    WHA! For all that is good and just, the K is being listed on Wiki as costing 128 million dollars each!?! That's crazy. Since there are a couple of years yet, maybe that will be cancelled, and the Osprey frozen as a specialized/MARSOC limited issue. But again, I think such Marine units use the Sea version of the Blackhawk anyway- although that probably changed because of the Osprey.
     
  11. DarthBoba

    DarthBoba Manager Emeritus star 9 VIP - Former Mod/RSA

    Registered:
    Jun 29, 2000
    Nah, the only Seahawk operators are the Navy. I believe the V-22 is quite deep into general issue, too. Obviously MARSOC/etc would have access to the HH-60H, but the V-22's range and speed would probably count quite abit against that, given how far away from conventional forces Force Recon typically operates.

    I'm not sure what's so expensive about the CH-53K, but then, it's not an airframe they buy alot of to begin with, and it is quite technically complex as it is with three engines and all the nav equipment in them.
     
  12. Mr44

    Mr44 VIP star 6 VIP - Former Mod/RSA

    Registered:
    May 21, 2002
    I think it has the making for a conspiracy theory there. Boeing kicks a couple of million per Osprey back to UTC, who then prices the CH-53K well, well, above market prices, which ensures a greater market share for the Osprey since the brass at the Marines want it anyway so they don't loose to the Navy....

    But seriously, I don't know either. I mean, even with a completely upgraded nav system, is the HUD alone supposed to cost as much as an entire other helicopter? Or is each of the 3 "hot-rodded" engines supposed to cost 20 million a piece? It's kind of crazy...
     
  13. DarthBoba

    DarthBoba Manager Emeritus star 9 VIP - Former Mod/RSA

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    Jun 29, 2000
  14. Mr44

    Mr44 VIP star 6 VIP - Former Mod/RSA

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    May 21, 2002
    That's what I was poking fun at though. The nature of such procurements. The increase itself isn't what I was dinging. (Blackhawk costing 6 million in the late 70's compared to about 20 million now, for example) It's about all the extra cool stuff that probably isn't needed. The E Stallion was probably the perfect version for the role it had within the Marines. The Marines would do quite well with an upgraded E, even increasing the price by 10-20% of 25 million, because it had everything it needed, and not much it didn't. I mean, the Air Force's J model only cost 40 million, and it had things like infrared, and low terrain radar, and GPS, and night vision. (and even after the J, the AF went with a specialized Osprey at even more money)

    Compare the Air Force para-rescue's J model at 40 million with all its features, to the Marine K model prototype at 128 million, and K model better be made from diamond coated paint and have solid gold controls or something. Or be able to fly Marines to the Moon and back if needed.
     
  15. DarthBoba

    DarthBoba Manager Emeritus star 9 VIP - Former Mod/RSA

    Registered:
    Jun 29, 2000
    Well, I imagine it probably will. Also-the MH-53Js are almost all rebuilds IIRC; they're not new aircraft, but remanufactured, which'd keep the cost down. Although the Air Force's habit of simply rebuilding 20-year-old airframes while all the other services buy genuinely new equipment for SOCOM irks me :p
     
  16. Alpha-Red

    Alpha-Red Chosen One star 7

    Registered:
    Apr 25, 2004
    That did happen not too long ago...bunch of insurgents broke into a U.S. base in Afghanistan and blew up a whole bunch of Harriers.
     
  17. DarthBoba

    DarthBoba Manager Emeritus star 9 VIP - Former Mod/RSA

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    Jun 29, 2000
    Found this to be interesting:

    French combat jump in Mali

    Not thousands of guys or anything, but I'm pretty sure this is the first combat jump any European army has conducted since WW2 or so.
     
  18. Mr44

    Mr44 VIP star 6 VIP - Former Mod/RSA

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    May 21, 2002
    Well, it might be a stretch to call it a "combat jump," but yeah maybe its fair to say it was the 1st jump into a hostile area since WWII.....

    What's funny is that now because of this, some in the EU are looking at the "re-organization potential of airborne troops....." It's interesting how cyclical these things are. So the French FF had a successful airborne operation undertaken under the GWOT. Not to diminish this, but the danger is that everyone and their brother will reorganize their peacekeeping forces under some "one size fits all" airborne model to save money, until some mission comes along where the limitations of airborne operations smacks them in the face, and it's Dien Bien Phu part deux-just instead of 1954, it's 2013.
     
  19. DarthBoba

    DarthBoba Manager Emeritus star 9 VIP - Former Mod/RSA

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    Jun 29, 2000
    D'oh. Forgot they jumped into Dien Bien Phu.

    Sure, there's limits to airborne operations, but there's limits to any lightly-armed expeditionary force and what it can do. Why the negative opinion, though? I mean, yeah, that could happen, but it's fairly rare that changes like that actually happen.
     
  20. Sarge

    Sarge Chosen One star 10

    Registered:
    Oct 4, 1998
    I'm not at all sure that rotating the prop/rotor without moving the engine will work better than tilting the engine. It's going to make a more complicated output shaft and transmission assembly between the engine gearbox and the rotor. That kind of complicated transmission always seems to cause severe developmental headaches and operational problems in aircraft.
     
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  21. DarthBoba

    DarthBoba Manager Emeritus star 9 VIP - Former Mod/RSA

    Registered:
    Jun 29, 2000
    Welcome to the thread, Sarge.
     
  22. Sarge

    Sarge Chosen One star 10

    Registered:
    Oct 4, 1998
    Thanks, DB. I don't keep up with mil tech like I used to since I retired 4 years ago, but I still like to take an occasional peek at what the young folk are up to these days.
     
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  23. DarthBoba

    DarthBoba Manager Emeritus star 9 VIP - Former Mod/RSA

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    Jun 29, 2000
  24. Alpha-Red

    Alpha-Red Chosen One star 7

    Registered:
    Apr 25, 2004
    Eh, that's an intelligence review? Seems like some rather basic stuff that you'd find on Wikipedia...and a rather boring read =/
     
  25. DarthBoba

    DarthBoba Manager Emeritus star 9 VIP - Former Mod/RSA

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    Jun 29, 2000
    Intelligence reviews aren't meant to be exciting or confusing, Alpha. :p