Anatomy of a Helicopter (non GSG anime related)

This is for all of you who know a thing or two about helicopters, like Full Metal Panic, and don't mind helping a fellow fan work out some technical issues.

I'm not really writing a lot these days due to a heavy duty term at school, but I've been considering going back to writing FMP fan fiction at some point. And that's brought back some issues I've had with the technical aspects of the series, in particular Mithril's MH-67 Pave Mare helicopters.

I should note I don't stick that close to canon on some of FMP's technical issues. The series can be unrealistic sometimes and also sometimes contradict itself. The last point especially makes me feel justified in sometimes tweaking things a little to make them more sensible.

So basically, here's one of the biggest questions. You have a helicopter designed to transport Armored Mobile Master Slave Systems like the M9 Gernsback as one of its primary roles. What sort of configuration makes the most sense for doing this and how the heck do you secure the payload to the helicopter?

Personally, I think a skycrane configuration makes the most sense, stowing a payload with the dimensions of an AS inside a helicopter's cabin seems a bit iffy to me. But I'm still left wondering how the hell you'd secure the underslung AS. How the hell do you attach a eight and a half meter tall, nine tonne payload to a helicopter and not make it unwieldly, particularly when you need to be able to load and unload it rapidly? I've wondered about using some of the M9's hardpoints as a linking system, but positioning a large helicopter and an AS with enough position to link up using the hardpoints seems like it would be really difficult.

There are other questions I have about the Pave Mare as well, but I figure this is one of the biggest ones and probably a good place to start...

All I know piero is that in the series they could make their herecopters go invisible So I Think they could have engineered a way to carry a gundam and let it go wuickly

Best bet would be to use a helo designed around a cargo container large enough to move the thing. The container would have all of the connections and such for start-up power and computer and radio uplinks, because keeping the pilot informed is important, execially before a drop. When they are on-target, the bottom of the container opens and the mech drops free.

I think a hardpoint mounting system could feasibly work. What you'd need would be some sort of flexible guide to line the fixing points up. I guess in the anime they showed the M9s stepping onto a mounting then being hoisted up.

Swinging back to canon again: the other thing is you see the M9s being deployed a couple of different ways, which also makes things hard. At the start of TSR they're dropped like bombs, but in the trailer short episode for that they're also thrown out the back of a C-17, which would suggest a possible dolly system of sorts. That would raise some intersting ways also of getting things lined up to mount the mech. You can manouver a wheeled bed pretty accurately, particularly with technologies like Smart Wheel coming online. In the field, maybe some sort of cable hoist and guidance system? Tension one side or the other to position the mountings?

Hmm, tricky design question that I've sadly not got the time to fully explore right now. Shall give it some more thought though.

We need LoC and/or Wil in this thread, stat.

having a background in attack aviation, not transportation, your guys' guess is about as good as mine. I've helped sling-load stuff, but that method of transport is rather insufficient for moving a 9-ton mech in combat-ready configuration.
Mav's idea seems as close as anything I could come up with. Cargo containers designed with a specific mech in mind (mounting to hardpoints inside), and a helo that hooks up to the outside of said containers like a crane claw. The problem with the way I envision it is... you'd wind up deploying mechs onto their faces from a few meters up unless the hardpoint mounting allowed for the mech to rotate downward from its shoulder mounts.
...need autocad for this stuff.

http://superrobotwar.files.wordpress.com/2009/05/srwhotnews_pla5_m92.jpg

Thought it might be good to have some pics of the M9 for reference as far as location of hardpoints was concerned. They've got some on the top sufaces of the mech too, actually. Of course, it might also be worth noting that it might make sense for the MH-67 to have been designed with the older, heavier, and bulkier M6 Bushnell in mind as payload, though that doesn't necessarily mean the carry methods for the diffferent mechs are the same.

A real world CH-53E Super Stallion can supposedly sling load up to 36,000 pounds, which is considerably more then nine tonnes. Of course, Super Stallions are fucking huge helicopters, and just because something can sling load that much weight doesn't mean it's ideal, especially as far as agility of the carrier aircraft is concerned. A payload that's flush to the aircraft seems much better.

In some respects I'm not keen on the cargo container system as it adds weight and you'd probably need to drop the container off then pick it up again in order to recover the mech in question. Not to mention it would have to be a container at least about two stories tall to fit an M9, even on hands and knees, which makes that payload seem awkward as well. On the other hand, though it is a flush fit, it would make it possible for the pilot to leave the mech during long flights, and it sort of fits with the idea of having swappable mission modules. An airframe the size of the Pave Mare seems like it would be an ideal platform for many things, and the ability to reconfigure between a mech carrier, troop carrier, electronic warfare platform, and arial command post seems like a useful feature.

Although I've sometimes felt the De Danaan relies a little too much on the Pave Mares... it sometimes seems like there's a real lack of any smaller transport helicopters among it's air assets. (That was one of the other issues I'd felt might be worth talking about.)

Hope I'm not overwhelming people here. There's a lot of different factors floating around at the moment...

honestly, I can barely remember what the MH-67 looks like in the series... can't seem to find any screen shots of it, either.

...but as to a helicopter's size... you're not gonna be able to easily lift 9 metric tons with any regular sized chopper. The 'black technology' plot device aside, a helicopter needs to be damn near the size of a Chinook to even take off carrying over 19,000 pounds... and even a Chinook would be feeling that much weight pretty badly.
You want maneuverability in the air with something that heavy? You need a plot device, plain and simple.

The FMP universe does have more advanced turbine engines. Though I still feel that logically, a helicopter like the Pave Mare should have had Kamov type contra-rotating main rotors instead of a conventional main and tail set up, so that it could make more efficient use of engine power. Then again, the aforementioned Super Stallion is a real life heavy lift helicopter and has more conventional rotors.

My phrasing there probably wasn't very good. I seriously doubt a fully loaded Pave Mare would be very agile. However, having the payload carried flush definitely has advantages over swinging it around like a pendulum.

Just as a note in case you were confused, I wasn't suggesting using smaller helicopters for AS transport. That role obviously requires a heavy lift chopper. I do wonder however if the lack of smaller transports leaves a capability gap in other roles.

Here are three shots of the MH-67 as portrayed in the anime. Apologies for the subtitles in one shot, but I only have DVDs, one, two and seven with me here in residence. The rest are at home, so I had to resort to another method to get screenshots.







I don't see the any sign of the side mounted miniguns that featured in the novels. It is interesting to note however that they've got considerable vertical height.

The JSDF helicopters in the A21 arc took a somewhat different approach with external payloads. (Note the heavier and bulkier second gen ASes being carried here as opposed to the third gen M9s.) I think this approach actually makes some sense, but wonder how you'd achieve the necessary precision for the link up stage.

What you want and need are two different things. A super-flit helicopter with the ability to defend itself does not exist, nor can it.


Sikorsky CH-54 Sky Crane Helicopter

While picking up and dropping cargo/men, its vulnerable. You would require an escort of smaller attack copters to defend it, simillarly how escort fighter planes go with bombers and cargo planes during war time.

Agreed.

Transport helicopters are sitting ducks when they land, load up or take off. This is mainly because they are built to be powerful and not to be agile as a combat helicopter.

Half of the protection on a combat helicopter is its maneuverability and speed. Sure you could out fit a transport with some turrets so it can defend itself, but that will still make it an easy target for the enemy because it will be stationary most of the times.

One of the reasons why WWII B17's were still escorted despite the fact that a B17 had gunner turrets on latterly every side of it. (Top, button, nose, tail, sides)

But the enemy attacking a B17 will be in the advantage because he will be on the move continuously and never in a straight line. a B17 would fly in a straight line, so while the enemy fighter can only attack head on. the B17's gunners will also have to cope with the enemy disappearing from view and then suddenly appear again on a side they weren't looking.

It only gets worse when its multiple targets zipping past you. Think of it as you being the B17 and a few bees that are buzzing around you being the enemy fighters.

So are the mechas carried inside the MH-67? They seem to have a large cargo hold.

What you probably would be looking at is something either like a CH-54 Sky Crane or a CH-47 with the cabin between the two rotors removed and replaced with a boom like the CH-54.

You'd load and transport the mecha flat (belly-side down) with mounts on the shoulder that would allow the mecha to swing forward as the legs were lowered until the mecha was in a standing position. You'd then remote disconnect the cables holding the feet and lower it a short distance using the shoulder mounts until it was on the ground, at which point the shoulder cables would disconnect and the mecha was free to maneuver.

Clearly, you couldn't really do this in a hot LZ unless you had attack choppers around to suppress enemy fire as you're probably looking at upwards of a five minute drop procedure. But since the Mecha can maneuver on their own, dropping them a safe distance away and letting them ingress on their own power shouldn't be a problem.

For field recovery, you'd need a human crew to attach the cables, then just do the reverse of the deployment - jack up the shoulders to get it off the ground and then pull in the feet until it's horizontal again and egress.

Yeah well, The mecha in FMP can still operate their arms when suspended from a transport, provided that the transport pilot can compensate for the shifting of weight. That and like a human, those mecha's can survive the plunge from quite a bit of altitude. So the helicopter would only have to be at an acceptable altitude to just release the mecha like a bomber aircraft would a bomb. From there on out its the mecha pilot that makes sure that the mecha lands without leg damage. Simple act of retracting the legs a bit upon impact like we would do when we job off a ledge or something like that.

Well that would make it even easier, then. Just load and transport them horizontally and drop them.

You'd need two sets of choppers for recovery - one to bring in the transporter-erectors (and crew) necessary to get the mecha back to horizontal and then a second chopper to load the mecha aboard and transport.

Not really. the transports for the mecha's are designated transports. the swing arms for the mecha are fitted so that the Helicopter can operate them. Its just a matter of hovering above the mecha, extending the swing arm, attach, liftoff, swing and close the bay doors.

Its not like Evangeline where you need a crew to load the mecha into a transport. That and the helicopters in FMP belonging to Mithril(Which Sousuke Sagara is a Mecha pilot for) are fitted with a stealth-field which basically makes the Helicopter invisible to the necked eye and some of the old radar tech. In the FMP Universe, there are only a few highly advanced surface to air missiles that are able to track a stealthed craft.


The aerial deployment of a mecha can be easily compaired with a paratrooper jumping out of a plane; Feet first!


NOTE: When Mithril is loading up inside the their submarine, then a crew needs to help because there isn't really enough room to have the Helicopter hover above the mech.

Third generation Arm Slaves like the M9 can survive significant drops (though they are sometimes equipped with parachutes, so I imagine there's a limit). I suspect the Second Generation models most organisations are using (and which I personally think it would be logical for the MH-67 to have originally been designed to handle) are quite a bit less capable in that regard however. That being said, I don't think it's illogical for the MH-67 to have been modified for use with the M9, I think it's just worth considering that might not have been the original intended payload.

As mentioned before, I think a Skycrane type configuration is very logical for a helicopter of this type. I think a cross between a Ch-54 and a Kamov naval helicopter, but larger in size then either of them, would make sense here. And assuming that the AS handling equipment could either get out of the way or easily be removed, you could probably make it capable of accepting 'mission modules' for other roles, like troop transporting or electronic warfare, which would be a major boon.

I still wonder if it might be possible to do something with the upper torso hardpoints. Wondering about maneuvering the bird so that got it's back end just above the mech in question then relying on the mech's pilot to get the final positioning done. Course, that would leave the legs dangling below the helicopter in flight (unless maybe you brought the knees up to the torso), but that's stil far better then hanging something below the helicopter on a cable. And hopefully it could be done fairly fast. The TDD-1 doesn't have a lot of Pave Mares, they're big and take up a lot of deck space. I think it's important that each Pave Mare be able to deploy and recover an AS on it's own.

I know canonically the Pave Mares carry the M9s internally, but that seems suspect to me given the M9s large size and weight. (Something like eight and a half meters tall and nine and a half tonnes or so in weight. Even on hands and knees, they've got a lot of vertical height.)

Also, I'm well aware of the unsuitability of heavly loaded heavy lift helicopters for combat. However, that doesn't stop them from mounting light defensive armament in real life. I don't think the side mounted miniguns described in the novels are an unreasonable feature.

Just continuing on a bit with the last statement I made in my above post... I think I already mentioned this, but it seems to me that the TDD-1s helicopter assets have a pretty big capability gap. Canonically, TDD-1 carries two types of helicopters, RAH-66 Commanches (why these exist when passive stealth was supposedly largely killed by the development of active camouflage in the FMP universe, don't ask me) and MH-67 Pave Mares. Now, the Pave Mare seems to me like an excellent platform for some applications, but the fact remains, it's a fairly large and heavy helicopter. After all, it needs to be able to transport a nine and a half ton payload a considerable distance, and if it was in fact originally developed for the older second gen Arm Slaves, then it's payload carrying capability might even be considerably higher then that. In fact, I wouldn't consider a maximum payload of 30,000+ pounds out of the question for such a helicopter. Those things are big.

Now, maybe this is just my inexperience with helicopter operations showing, but doesn't it seem like such a large helicopter might not be very suitable for a lot of missions? Particularly the one's carried out by the TDD-1s PRT? (Note: PRT stands for Primary Response Team, and are essentially the TDD-1s infantry complement. The Arm Slaves are part of the SRT, or Special Response Team.)

*shrug* all I've really seen 'em used for is dropping off/picking up ASes or troops. 'bout the only real reasons to use a smaller helicopter for those things (ie Black Hawk over Chinook IRL) are
1- the smaller helicopter is a somewhat harder target for handheld rocketry (when hovering or grounded, anyway) and
2- the smaller helicopters are cheaper not quite as ridiculously expensive and more widely available.

larger, more powerful helicopters tend to be faster, tougher, more maneuverable, and far more capable for hauling a load. If Mithril had tight budget constraints, there'd be good reason. As they are, the only helicopters they need are 1-heavy mover and 2-recon/gunship. no need for a crossover/multirole chopper in there. if they need mobile C&C, they can deploy AWACS... which tend to be high-flying fixed-wing aircraft.
their layout makes perfect sense to me.

In a clearly AU piece of FMP fanfiction that I wrote in the past, I actually had the De Danaan operating a combination of Pave Mares and Blackhawk variants rather then the canon Pave Mare/Commanche combination (I guess I felt the clearly AU nature of said fanfic allowed me some liberty with those sorts of details). I guess as I saw it a Blackhawk variant equipped with external stores stations and proper sensors could do the scout/attack mission just fine and would have a useful personnel transport capability as well. Plus longer range, which could be useful for operations that required flying far inland.

But then, I suppose the De Danaan's lack of personnel transport capability is partly an artificial construction on my part. Much as I may think the MH-67 should be a skycrane type design, it's canon that they carry Arm Slaves internally and can act as troop transports at the same time.

(Returning to that subject for a moment -it occurs to me that a M9 flat on it's back or belly wouldn't have a lot of vertical height and could fit into a helicopter's cabin if the cabin were long enough (say a bit over thirty feet). The problem would be getting the thing on and off quickly in that position. Trying to have the AS get itself into such a place and position under it's own power strikes me as a recipe for a damaged transport helicopter.)

It also occurs to me though that the De Danaan's Commanches might not have been present in the original novels, though I can't verify that without my copies of the first three novels (they're at home, I'm in residence). I'm pretty sure the Pave Mares took an observation platform sort of role on more then one ocassion in the later novels though. Personally, I think the addition of a smaller helicopter for the scout/attack role in the anime made a lot of sense, even if I don't entirely agree with the model that was chosen.

The Commanche was designed more to be a scout chopper than an attack chopper - it's hard to make something stealthy when it has large amount of armament hanging off it.

It's possible the Commanches fill that roll in the FMP universe and the passive stealth may have been augmented with active systems. They check the area to ensure it's safe for the MH-67s to operate.

regarding the Comanche: would've made one helluva replacement for the Kiowa.

also, for stealth purposes... as far as I know, active camouflage does little to cover up sound... and anyone who has been around 'em will tell you that Black Hawks' rotors are effing loud (you can hear 'em coming from several miles out). That was the beauty of the RAH-66 prototype. Not only did it have a radar signature the size of a small bird, it made about as much noise as that bird.

In some respects, the Commanche's low noise signature seems like a more useful feature then it's radar-related stealth features, considering that helicopters seem to tend to operate at low altitude anyway. I have serious doubts that the Commanche in it's real world form would exist in the FMP universe though. After all, if ECS equipped B-1s were built instead of the B-2, why would the Commanche project have kept it's passive stealth features?

Also, I was under the impression that the noise signature of existing helicopters could be reduced significantly through the installation of modified rotor blades. Am I wrong on that?

Modified rotor blades would help, but the RH-66 program did incorporate a number of noise-reduction systems (in addition to blades) which holistically provided a significantly reduced noise signature.

I expect the main reason the RH-66 was cancelled was that UAVs worked as well (if not better) and they're cheaper to operate and cheaper to lose. The same probably applies to the FMP universe.

true. makes you feel kinda sorry for adrenaline-junkie combat pilots: