Your Nation's Air Force Mark III: Best Korea Edition

[The Technocratic Syndicalists]

With this talk of rotor blade-mounted antennas, would there be any merit to the concept of an end-fire antenna located in the hub fairing?

Lots of the concept designs for LHX and the like had hub fairings of some sort covering the rotor hub itself and some of them were relatively large. It wouldn't provide anywhere near the surface area of a rotor blade antenna, but depending on size it might still provide more space than a mast pod while also providing 360 coverage like the rotor blade.



Also, would there be any utility in adapting some of the optical recognition/rangefinding technologies used in self-driving vehicles to a collision-avoidance system for helicopters?

The loss figures in the study Kyiv posted indicated that the vast majority of losses were to mishaps and mechanical issues and one of the largest factors was accidental collisions or damaging impacts with local terrain or obstacles. A better situational awareness system was identified as desirable and while low-power radars spaced around the aircraft are probably the most straightforward solution (and AFAIK the most common solution for consumer collision alert systems), they might not be desirable for a combat helicopter wanting to control its emissions. Optical and other passive ranging systems though have made strides as of late but I'm not sure how suitable they'd be, especially against small hazards like wires/cables that would be very difficult to spot (and might even be problematic for radar detection). Perhaps a laser system would be a compromise between performance, cost, and detectability, although it would have a limited field of view.

The goal would be to create a system that would alert the pilot if he is approaching too close to an obstacle, especially one outside of his normal field of view. And possibly even include an auto-GCAS feature to react immediately in the event the pilot doesn't react in time.

The drone versions of the KMAX, blackhawk and MH-6 used LiDAR obstacle avoidance systems. It's probably the same technology as the google self driving cars I see around my town that have a visible spinning LiDAR system mounted on the roof. LiDAR ground collision avoidance (GCAS) systems are also quite common on smaller fixed wing UAVs. LiDAR is definetly better for covertness since the beamwidth and sidelobes are much smaller than even a MMW radar. For helicopters LiDAR is also very desirable because it has the resolution necessary to spot power lines that a radar or optical system would find very hard to detect.

Bell's concept V-280 uses an EO/DAS system (with multiple MWIR/LWIR IR imagers placed around the aircraft) connected to an HMD very much like the F-35 that in addition to letting the pilot "see" through the plane can act as a MAWS and I presume also as an optical collision avoidance system. It seems like a system extremely well suited for helicopter/tiltrotor use since it drastically improves situational awareness, something which could certainly help prevent crashes and shootdowns.

[Austrasien]

1. Most of the HELLAS box is space for the gimbaling and scanning optics AFAICT. Using flash LIDAR would be an option but it would increase the cost substantially. US research with unrelated LIDARs for helicopter landing in brownout conditions have used stored images that are captured on final approach. This seems to work pretty well.
2. I have no idea. It was a short entry in the export catalogue without much context. Helicopter blade radar would be fun, but a long narrow antenna like that is a very poor choice for 3D tracking. Speculatively it could be used in combination with an optical warning sensor to provide accurate range/doppler to the accurate tracking of the optical sensor. But radar/optical sensor fusion is not the most reliable thing.

[The Technocratic Syndicalists]

This is a design for a canard rotor/wing gunship I did a while back that I've sort of put on the backburner until this discussion prompted me to go back and look at it. I think I wanted a FLIR turret in the nose and a four faced AESA attack radar in the rotor fairing. The faring under the chin IIRC was supposed to be for a 30mm chaingun that could rotate into the fairing when not in use to minimize the craft's RCS like the 20mm cannon on the RAH-66. I was also determined to put a AN/ALQ-180 "COMPASS HAMMER" type blinding laser system in the 10-20 kW range that could detect and blind/fry hostile optical sensors but I forgot where it was supposed to go. It would preferably have 360 degree coverage around the aircraft so perhaps a VLO shaped pod under the fuselage behind the chaingun fairing was what I decided on, placed in between the two internal missile/rocket bays.

[Gallan Systems]

Compass Hammer was mounted on the belly of an F-4 in a weapons pod, probably a converted fuel tank. It would be carried by F-15Es to protect against AAA during low level attacks. A better solution is to simply fly above the net of AAA and MPADS, which is what happened after Desert Storm.

Cameo Bluejay was the Apache equivalent. It wasn't anything related to Compass Hammer/Coronet Prince, it was literally AN/VLQ-7 on a helicopter. The HMMWV version was called "Outrider" and there are goofy pictures of it in an old magazine article somewhere on the Internet. I don't know if Martin Marietta built Cameo Bluejay IRL, it would have required a lot of miniaturization from the bulky prototypes built in the 80s.

It doesn't matter though. Apache has already demonstrated a self-defense laser capability: http://newatlas.com/go/7461/

[The Technocratic Syndicalists]

Compass Hammer was mounted on the belly of an F-4 in a weapons pod, probably a converted fuel tank. It would be carried by F-15Es to protect against AAA during low level attacks. A better solution is to simply fly above the net of AAA and MPADS, which is what happened after Desert Storm.

Cameo Bluejay was the Apache equivalent. It wasn't anything related to Compass Hammer/Coronet Prince, it was literally AN/VLQ-7 on a helicopter. The HMMWV version was called "Outrider" and there are goofy pictures of it in an old magazine article somewhere on the Internet. I don't know if Martin Marietta built Cameo Bluejay IRL, it would have required a lot of miniaturization from the bulky prototypes built in the 80s.

It doesn't matter though. Apache has already demonstrated a self-defense laser capability: http://newatlas.com/go/7461/

What I'm interested in is something more powerful than DIRCM, something like ALQ-80 or VLQ-7 which can actually "blind" hostile sensors. From what I understand how it works is first does a sweep with a low power beam and when it gets a reflection from an optical sensor, like an IRST or the seeker of a MANPADS, it instantly switches the beam to max power to either blind or if it's powerful enough, fry the threat seeker. Unlike a DIRCM it's not purely a defensive system, its powerful enough to blind/fry the seekers on hostile vehicles at tactically relevant ranges. So not only can it defeat MANPADS but optically guided AAA/SPAAGs, amongst other things where unlike a fixed wing craft the helicopter can't simply "fly over" them. For this I'm thinking a solid state Nd:YAG laser in the 10-20kw range. It would probably be contained in a pod with a ram-air turbine, batteries, and the beam forming equipment. IIRC this type of system would be very controversial IRL and get a lot of bad press because the laser could theoretically permanently blind people looking through binoculars or NVGs if the beam sweeps over them which is pretty gruesome but actually technically isn't covered by the UN blinding laser convention (which only applies to "un-augmented" vision) but this is NS so nobody cares. I'm also interested in something like the AN/ALQ-165 ASPJ mounted in wing tip pods on the stubwings to deal with threat radars that the laser obviously doesn't cover.

[Gallan Systems]

It's ALQ-179 and ALQ-180.

Compass Hammer is the blinding laser.
Coronet Prince is the scanning/target locating laser.

The jamming pod combined them into a single system.

The problem with these kinda stupid 1980s retroreflection targeting systems is that glass exists and exists in copious quantities on a battlefield in an urban area. You're going to be constantly attacking glass shards and stuff instead of threat optics. There was never a real solution offered that satisfactorily solved this problem. I suspect you could target based on optical warning receivers (how DIRCM works), but MAWS have their own problems, and that doesn't require a high powered laser. It's one reason why everyone agreed that blinding lasers were worth the ban and consented to it without much fuss.

DIRCM for blinding missile seekers is better than blinding lasers for self-protection. For an offensive electro-optical denial mission, blinding lasers have some use, but this puts them in the realm of tactical jammers and ESM targeting systems, not self defense pods.

[The Technocratic Syndicalists]

It's ALQ-179 and ALQ-180.

Compass Hammer is the blinding laser.
Coronet Prince is the scanning/target locating laser.

The jamming pod combined them into a single system.

The problem with these kinda stupid 1980s retroreflection targeting systems is that glass exists and exists in copious quantities on a battlefield in an urban area. You're going to be constantly attacking glass shards and stuff instead of threat optics. There was never a real solution offered that satisfactorily solved this problem. I suspect you could target based on optical warning receivers (how DIRCM works), but MAWS have their own problems, and that doesn't require a high powered laser. It's one reason why everyone agreed that blinding lasers were worth the ban and consented to it without much fuss.

I'm thinking the scan could be limited to a predefined target, like the helicopter detects a ground vehicle with its FLIR or radar and then sweeps over with it with the laser. I haven't read much into how the reflection detection system works but based on how the laser is refracted I would presume you could filter out glass shards and what not and just target magnified optical windows which is what every IRST or IR seeker has. Now if the laser is really powerful, say in the 50kW range, you could burn out the seekers of both IR and radar guided missiles and potentially disable vehicles or small aircraft, something that could be useful. GA says they can make a 150kW laser than can fit into the payload bay of a GE Avenger so a helicopter mounting could potentially be viable.

[Gallan Systems]

Stingray just looked for glass. Coronet Prince looked for AAA muzzle flashes and swept its laser around them to look for glass optics.

In which case it's literally a DIRCM. Permanent destruction of EO is nice but it requires a large and bulky weapon system (Stingray isn't fitting in a wingtip), and temporary blindness can achieve similar results for self-defense. Not sure how you'd "burn out" the seeker of a RF missile with a laser, though. That would require structural damage that might just make the whole thing fall apart. In which case you've invented a laser gun that's actually useful.

GA makes Avenger. Did you switch those around?

[The Technocratic Syndicalists]

Stingray just looked for glass. Coronet Prince looked for AAA muzzle flashes and swept its laser around them to look for glass optics.

In which case it's literally a DIRCM. Permanent destruction of EO is nice but it requires a large and bulky weapon system (Stingray isn't fitting in a wingtip), and temporary blindness can achieve similar results for self-defense. Not sure how you'd "burn out" the seeker of a RF missile with a laser, though. That would require structural damage that might just make the whole thing fall apart. In which case you've invented a laser gun that's actually useful.

GA makes Avenger. Did you switch those around?

The laser just has to burn a hole in the missile's radome and let aerodynamic forces do the rest. Larger, faster missiles can have radomes made of thicker, ablative material but smaller SHORAD type missiles that the laser would be primarily be engaging probably aren't very "hardened" meaning a smaller laser could be sufficient. For what's its worth according to the USN a 150kW laser could burn through the radome of a supersonic ASCM which is why 150kW is mentioned as a target goal for naval laser weapon systems. A 150kW is probably too large for a helicopter but something in the 30-50kW range could be feasible.

You're right, GA makes both the laser and the avenger. I'm thinking the laser and all it's associated equipment will be in a detachable pod under the fuselage and the wingtips will carry the self-protection jammers.

[Gallan Systems]

AIM-7s are supersonic.

A helicopter has no real need for defense against radar guided missiles. Defense against infrared missiles, laser beamriders and optical/visual guns/missiles, and radar guided guns/missiles, in that order, are the most prudent objectives for a helicopter defense suite. Helicopters have a very limited area to mount defense systems. Generally they might be able to defend against one or two of those actively, unless you have a defense suite that is agnostic to targeting systems.

So consider QuickKill instead of Stingray.

But first, fix your helicopter. It looks like a GI Joe toy aka a coke-fueled 1980s concept art.

[The Technocratic Syndicalists]

AIM-7s are supersonic.

A helicopter has no real need for defense against radar guided missiles. Defense against infrared missiles, laser beamriders and optical/visual guns/missiles, and radar guided guns/missiles, in that order, are the most prudent objectives for a helicopter defense suite. Helicopters have a very limited area to mount defense systems. Generally they might be able to defend against one or two of those actively, unless you have a defense suite that is agnostic to targeting systems.

So consider QuickKill instead of Stingray.

I'd still like a compass hammer type system to screw with optically guided AAA and missiles. A supercharged DIRCM is probably sufficient for this and along with its power generation and targeting system can be carried in a pod. Some SHORADS are command-guided which is why I'm interested in radar jammers which can also be useful against radar guided AAA.

Another system I've been considering is something like Orbital ATK's helicopter APS which launches miniature rocket-powered kill vehicles from an ALE-47 flare/chaff dispenser to hit oncoming missiles.

The "helicopter" I have looks funky because it isn't technically a helicopter as it's a canard rotor/wing powered by two turbofan engines. It's works like a hot tip-jet which is why there's no presence of a tail rotor mechanism.

[Austrasien]

An excellent illustration of how optical augmentation sensors work. Note it is not actually *glass* but glass reflections from optical components within the sight focused by the optical system. It is possible with current technology to interrogate suspected optics with an extremely high sensitivity/range resolution receiver (photon counting) which can actually resolve the reflections from each lens inside a telescope, which produces a characteristic range pattern of returns that random clutter does not. This cannot be extended below the near IR band though because sufficiently sensitive detectors do not exist for longer wavelengths, requires a very powerful laser and is a slow method because each suspected return needs to be interrogated individually.

Optical augmentation works fairly well outside of densely populated areas though because few things in nature have comparable optical cross sections to the retroreflection from a telescope on-axis. US, Swedish and Canadian researchers have all shown typical optical sights can be detected on-axis in natural terrain from many kilometers away even by a human operator observing the reflections without any kind of special algorithms or processing with conventional cameras in the appropriate bands.

There is a major DARPA/USAF program that has been going on for a couple of years to develop better technology for this. But not much information about what they are actually going or what they have achieved.

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Blinding image sensors does not actually work because unless every detector is saturated it will still be able to track the center of the illumination. The energy needed to saturate all detectors is generally sufficient to physically damage the detectors near the focal point. For practical purposes there is no distinction between a dazzler and destructive countermeasures where staring image sensors are concerned.

Attacking the detector is not considered a very good strategy though because it requires an in-band laser capable of generating very high energy pulses. Which is easy for visible and near-IR, but basically limited to CO2 lasers for LWIR and almost non-existent (except for chemical lasers) in the MWIR band. And when possible countermeasures are considered the lasers need both high energy pulses and frequency agility. Multiple high energy frequency agile pulse lasers is a very unattractive proposition because even a single laser source in current DIRCMs already costs millions of dollars, and they are not sufficiently powerful.

It is likely that damaging IRCMs will be realized through mid-to-high energy lasers that attack the optics directly and craze them. Or perhaps that DIRCMs will be superseded entirely as the main line of defense entirely in favour of hard-kill countermeasures, much like what has occurred in ground vehicles. This may actually prove to be cheaper than the lasers needed to defeat IIR seekers.

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I could probably talk more about this but Zzzzzzzzz

[Gallan Systems]

TBF VLQ-7 is still a qt3.14 even if Trophy is a lot better.

But yeah, Israel will be the first country to lead the way in developing next gen helicopter defense probably. Thanks Fliker.

e: Don't rust &c. get your transmission fluid checked and don't forget to get your valve seals replaced.

[New Vihenia]

Great design! Never seen a configuration for a CAS aircraft like this before. I'm gonna assume the engines are high above the fuselage to prevent FOD getting into the engines and damaging them. Looks pretty rugged as well. Also seems to be a cannon under the belly as well. Great design!

thanks.

Though the engine placement is more like to promote Coanda effect to increase lift and thus shorten takeoff distance.

[Taihei Tengoku]

What is the feasibility of systems such as the XT908 or EDI "Extreme Deep Invader" within the airforce?

We're not there yet for AI technology. So it's unfeasible for it.
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Anyway.. i doodle myself a CAS aircraft :3

I call her Claudia Blitzvogel

Feel like the engines would soak up a lot of AAA, given that it's near center mass and exposed. Removing the engine pods might be troublesome considering that there's important bits nearby (unlike A-10) nor can you just pull it out the back (unlike Su-25).

[Pavelania]

We're not there yet for AI technology. So it's unfeasible for it.
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Anyway.. i doodle myself a CAS aircraft :3

I call her Claudia Blitzvogel

Feel like the engines would soak up a lot of AAA, given that it's near center mass and exposed. Removing the engine pods might be troublesome considering that there's important bits nearby (like A-10) nor can you just pull it out the back (like Su-25).

Couldn't you just pull the engines forward to remove them?

[Iltica]

Or bury them in the wing roots with the exhaust peeking out on the top of the wing.

[New Vihenia]

Feel like the engines would soak up a lot of AAA, given that it's near center mass and exposed. Removing the engine pods might be troublesome considering that there's important bits nearby (unlike A-10) nor can you just pull it out the back (unlike Su-25).

Well then i face a dilemma on how to fullfill the STOL requirement.

[Iltica]

Blown flaps?

[New Vihenia]

Blown flaps?

yea and the simplest is put the engine on top. like An-72 did.

[Austrasien]

JATO
A
T
O

[Taihei Tengoku]

Thrust reversers maybe

[Austrasien]

STOL is not exactly essential.

[Gallan Systems]

Feel like the engines would soak up a lot of AAA, given that it's near center mass and exposed. Removing the engine pods might be troublesome considering that there's important bits nearby (unlike A-10) nor can you just pull it out the back (unlike Su-25).

Well then i face a dilemma on how to fullfill the STOL requirement.

TVC and Thrust Cult.

[Iltica]

Blown flaps?

yea and the simplest is put the engine on top. like An-72 did.

And the easiest to shoot 30mm rounds into. Bleeding air from inboard engines is more complicated but may have a greater effect since the exhaust is spread across the wing instead of just the area just behind the engine.
If you are dead set on external engines, it is also possible blow flaps externally from engines mounted under the wing with a series of slots like so: