Attack Helicopters combat survivability

TR1 wrote:

magnumcromagnon wrote:

Speaking about poor hit probability, here's some more footage of Apache chain-gun fire:



Why have such an inaccurate weapon in the first place? I agree a grenade launcher makes rather more sense than an inaccurate chain-gun, add a few hundred grenade launcher rounds to Mil-24/35's storage compartment as well as a ammunition feeding system connecting the compartment with the grenade launcher and you have a weapon system designed to engage insurgent/technicals that is significantly more cost-effective than the chain-gun.

Wow. That video proves just how important helicopter armor can be.

The comments are just gold, how uneducated and ignorant people can be.

Some people who have never fired a real gun think the bullets all go where the crosshair is on the screen.

Equally some expect sniper accuracy from all weapon types including machine guns.

With 30mm HE ammo you don't need a chest hit to kill but impacting rounds 10m away are not good enough to be effective.

The cannon on attack helos are not designed to kill individual soldiers... one shot one kill.

they are generally used against area targets or large relatively soft targets like trucks and light vehicles... targets 4-5 metres or more long and 2-3 metres high and 3-5m wide.

Against enemy troops often rockets will be fired and large groups will be engaged using the wide shrapnel spread to ensure efficient coverage of open areas without precise aiming.

the Hind went for light rockets carried in large numbers for the job with 57mm rockets having warheads of only about 800 grammes of HE which doesn't sound like very much but is actually about 10 times more than is in most attack hand grenades.

In the cases of videos shown however Rockets could not be used due to proximity of friendly forces and civilians or neutrals.

Ideally you want a guided weapon but without the enormous expense of ATGMs like Hellfire and Trigat ER. The laser homing add on kits for unguided rockets would be ideal in this situation with maybe 2-3 rockets needed in each video where each rocket could have taken out several enemy combatants at one time with the laser precisely positioned to shower the target individuals with heavy fragments... when using 80mm rockets (Soviet... 70mm western) the HE payload is about 4-6kgs which would be very lethal out to 10-15 metres around the point of impact.

Garry, i said it before and i say it again.

In case of Apache the problem is not just, and not primarily the low accuracy, the problem is, it uses expensive HEDP (HEAT grenandes) which have poor capabilities compared with their M799 HEI rounds with higher explosive charge and more fragmentation.

And like in the video that was posted by magnum, in that one engagement where the pilot was left with only 66 rounds left he only could bring the one guy down because of a DIRECT impact on his torso while all other HEDP M789 rounds where impacting only few centimeters next to him.

Poor discipline in CAS mission, jerking with the gun while shooting so he losses his target out of side and shoots 50-70 meters far away from his target just to adjust the crosshair back on target.

BlackArrow wrote:

A source please for this information on the Tiger's gun.

Not only that you can clearly see the difference from the accuracy of the GIAT 30 M781.

Here promo video for Tiger helicopter that was used as advertizment, the gun fire in front engagement is quite amazing in accuracy hitting small targets.



While the video of real combat where they shoot off-bore with a calibre that has to high recoil for the weight of the helicopter, it completley goes out of the figure of its 4m CEP, in this video it has CEP of 10+m.



So there is no point in having a to overpowered gun on your to leight weight aircraft.

BlackArrow wrote:I am. I'd say the gun on an Apache is a lot more accurate than the gun on a MiG-29 or F-16.

You are wrong on that account, longer barrel, higher propellant = higher accuracy, but that is irrelevant because you just made a rather nonsensical comperision between a helicopter and an aircraft that is not considered by its gun accuracy but only about pilots dogfight capabilities and how well his training and experience reflects and are used in real combat.

BlackArrow wrote:The AH-64 does have some armour. It's very unlikely an Apache - or any other military helicopter - could be downed by fire from an assault rifle.

It already has been downed by 7.62mm fire while Mi-24 which has even less armor than Mi-28 was never downed from lower than 12.7mm massive fire among those where higher calibres such as 14.5mm and 23mm used in afghanistan, which today is not the case for Apaches flying in Afghanistan.

The problem is Apache has very big windshields which are not armored, so the pilots are exposed and aircrafts getting shot at with a variety of weapons and calibres. Non bulletproof glass will not stop fragmentation of exploding MANPADS or 23mm HE-FI rounds against the helicopters armor.

And it makes you wonder why Apache glass is not designed to withstand AK fire.

The main problem is their size... if you want bullet proof then it is going to be at least 50mm thick which would make them very heavy and less transparent.

The front transparency on a Hind will stop 23mm HEI rounds, but the curved canopies are not bullet proof and there were plenty of claims that several were shot down from above by rifle fire... of course the same claims that an Apache was shot down by rifle fire was immediately ridiculed by western observers in Iraq... which is amusing considering western claims the Afghans did the same in the 1980s with 303 rifles.

In case of Apache the problem is not just, and not primarily the low accuracy, the problem is, it uses expensive HEDP (HEAT grenandes) which have poor capabilities compared with their M799 HEI rounds with higher explosive charge and more fragmentation.

The wrong payload for the wrong war... sounds pretty typical.

HE Frag rounds would be much more appropriate and more effective... on the rare occasion they come against armour they could use Hellfires anyway...

As this is the Mi-28 thread I would point out that the 30mm cannon on the Mi-28 is dual feed and is normally equipped with HE and AP ammo in separate belts so the gunner can decide with a flick of a switch which ammo type to use. the new Mi-28M will have the ammo moved from the sides of the gun to inside the aircraft to allow more ammo to be carried in a much more aerodynamic configuration. Also the cockpit transparencies are much smaller and armoured to stop 14.5mm HMG rounds from about 10m... which pretty much suggests to me that it is small arms proof.

I am. I'd say the gun on an Apache is a lot more accurate than the gun on a MiG-29 or F-16.

You are comparing a machine gun with shot guns...

The gun of the Apache is a low velocity weapon with heavy projectiles that fires at a low rate of fire to help keep the weapon on target. Ground targets don't need high velocity or high rate of fire weapons. Aircraft cannon on the other hand require very high rates of fire and benefit from higher muzzle velocities to hit small fast moving manouvering targets.

the fixed gun mount of fighter aircraft and the recoil to weight ratio means they are probably rather more accurate for longer bursts.

In comparison the cannon on a helo turned 90 degrees to one side will effect the stability of the aircraft because the gun is not mounted on the centre of gravity and the recoil is considerable.

I think the main problem was the Apache got too close to the ground - and to enemy fire, didn't keep his distance. Officially no Apache has been lost to enemy fire in Afghanistan.

Helicopters have to operate at low level and in environments like Afghanistan there is no clear lines on a map showing where insurgents are or are not.

If you want to fly the Apache at medium altitude firing Hellfires from 6-8km range then you might as well use F-16s with LGBs...

mutantsushi wrote:Is there any reason why gun turrets aren't mounted at the Center of Gravity (at least in 2 dimensions), rather than under the nose?
That seems like it would at least help when firing at high angles from the nose pointing direction...?

This is the reason look at the angle of the helicopters from nose to tail rotor.









The reasons for this are like followed:

- helicopters are designed to have a center gravity which effects the design in such a manner that the nose is higher than the belly and tail rotor, to counter the bullky and heavy front section compared to the less fat after section. Through this design the helicopter can start and land without the pilot needing a full cyclic counter move to avoid strucking the ground with tail or nose.

- Like you can see on all those pictures posted, all guns are facing upwards and this is needed since a gun on Attack Helicopters is mainly there to have the Range advantage over ground based small arms to high powered calibres. If you would mount the turret right under the belly at the gravity center the gun could only point in horizontal sphere and never up, to avoid to struck the fuselage while firing. That would mean your range is greatly reduced just because your gun is under the belly and can only fire horizontal or downwards.
Such a design would destroy the main purpose of the high calibres of the gun and cripple its range dangerously to the range of ground based AA weapons.

- One other point is that at the center there are flight control mechanisms, fuel pumps,fuel tanks, hydraulic tanks for the landing gear. So if the helicopter is damaged or losses engine and has to crash land the turret will slam through the belly into the fuel tanks and can lead to more trouble than the pilots already had experienced. An american observation of crash landings has shown that there is a significant number of dead pilots because of fires that were breaking out after the helicopter has crashed and pilots couldn't bail out due broken bones or losing consciousness.


That are the main reasons why we don't see gun turrets at the gravity center installed.

Very simply the centre of gravity on a helicopter is directly under the main rotor on the lower fuselage.

the only helo that comes close is the Ka-50/52 family of helicopters where the guns are horizontally in line with the cg but not vertically in line.

the result is a much more accurate weapon but rather more limited traverse capability.

Fortunately for the Kamov the coaxial main rotor system makes the lack of traverse unimportant... on a standard helo with a tail rotor at high speed the tail rotor becomes ineffective because the air flowing over the sides of the aircraft keep the aircraft pointed in that direction while the air flowing sideways over the tail rotor is much less effective at applying a side force... which means to turn a helicopter flying forward at high speed it needs to roll like an aeroplane instead of just yawing using the tail rotor (on a conventional plane there is the same problem as with high forward speed the ability of the rudder in the vertical tail fin has less and less effect at turning the aircraft.

the coaxial design of the Kamov means that there are enormous turning forces available because each set of main rotors has a lot of momentum which can be used for pedal turns even at high forward speed.

this means that even at very high speed in any direction the Kamov is able to turn its nose (and its gun) to point at targets.

to put is simply an apache helicopter with a nose mounted 30mm gun is like firing a pistol with outstretched hands... pointing forward means recoil is absorbed and the shooting is pretty accurate, but the Apache rarely hovers because that would make it an easy target for RPGs and small arms fire, so if it is not hovering then it needs to orbit its targets which means it can't fire straight forward any more... it has to shoot sideways... think of the effect of arms stretched forward holding a 45 cal pistol but shooting and looking sideways... your outstretched arms are weak at absorbing recoil from the side...

Ironically despite being called a Gun ship most attack helos only use their guns occasionally in COIN type operations because in a serious war getting that close to enemy troops that could be equipped with all sorts of missiles is very dangerous... anyone with an ATGM could point it up at your helicopter and have a decent chance of doing serious damage... especially with those ATGMs that can be fitted with HE Frag warheads for non armoured targets.


As mentioned previously the guns with the highest recoil are generally the ones with high velocity shells and very high rates of fire which are not suited to air to ground use.

One of the best helicopter mounted cannon today would be the twin barrel 23mm cannon fitted to the late model Hinds. The projectile is the same round used in the ZSU-23-4 which is very effective at bringing down aircraft. the main difference is that in the Shilka the shell case is 152mm long and the larger propellent charge generates a lot more recoil and velocity.

The 23mm gun on the new Hinds use the 114mm shell case of the 14.5mm HMG.

this means cannon performance HE shell from a compact HMG ammo sized round.

The result is a heavy HE projectile delivered at moderate velocities at very high rates of fire in a small compact round that can be carried in large numbers.

Geronimo wrote:
Sorry but this is false, the gun on the Tiger was designed to shoot from -90° to +90° and as you can see in the following video from 0:50 to 1:05, Tiger crews fully take advantage of the turreted gun, there is no restriction with the use of the turret.
Mali War 2013 : https://www.youtube.com/watch?v=gW_EmN76NK0
The video was recorded by a UAV and you can see a Tiger helicopter engaging two enemy vehicles with the turreted gun as the helicopter flies into the village.

How a helicopter is designed and how it performce are two different things.

Geronimo wrote:
In fact, during the first operational deployment of the Tiger (Afghanistan 2009) after a few engagements Tiger crews realized that, unexpectedly, their gunnery was even more accurate at +/- 90° than in front of the gunship.

That is physically not even possible and every video of every gunship/attack helicopter proofs otherwise. Shooting alongside with the traveling direction stabilizes the gun and absorbs the recoil very effeciently into the plattform. Shooting with high calibres which create high recoil, off bore, with leight weight aircrafts create a higher scattering and destabilize the trajectory and in case of tiger helicopters even cracks have been reported at the nose section and this problem was even addressed in the debate of our German UHT since there are lot of people who wanted the M871 30mm like the french have.

Geronimo wrote:So, they developed tactics where they would sometimes fly in circles around the talibans, shooting them with the 30mm gun, without coming close.
Concerning  the accuracy or inaccuracy of the Tiger, it is directly linked with the combat experience and the coordination between the pilot and the gunner.

Just for your information, conventional Main/tail rotored helicopters can ONLY fly in circles and shoot offbore to its target. If tail rotored helicopters had the sufficient torque they would "funnel" their target as the co-axial helicopters will do at high speeds, that would increase their accuracy at least by x2 factor.

Geronimo wrote:
In this video from Afghanistan, the distance is different : Army pilots are shooting from 2050m down to 950m (1st taliban KIA at 1750m, 2nd taliban KIA at 1250m). Also from the audio, I understand that the gunner noticed the two talibans escaping the area just 1 second before he started shooting the gun and he simply wanted to smash them, he was not competing for "gunner of the year" award. He was so filled with adrenalin that he even kept shooting the gun after the talibans were done.

That being said, I agree with you there is often a big difference between an advertisement and the reality of war. But this is normal, the stress level and the stakes are not the same.

I haven't critized the starting engagement at 2km mark, actually it is rather accurate than expected but that is because the azimuth to the helicopter itself is not 90° but more like 20° which still has some stabilisation from the directional flight of the helicopter. The closer the helicopter gets the less discipline they show which is another critic point of NATO troops in general, it is not like this is Afghanistan from the 80s where they were equipped with ATGMs and MANPADS, 14-.5mm and 23mm zsu.

Geronimo wrote:
Indeed, it seems counter-intuitive that the gun would be even more accurate at +/- 90° than at the front but this is how Tiger pilots described their gunnery experience in combat. According to Tiger crews, contrary to other gunships (like Apache), the Tiger can perform stabilized shooting not only in front of the gunship, but also on the sides.

Just because the crew says something doesn't mean its true.

An Apache crew pilot lied about the Apache to a video crew in some documentary that the Apache has bulletproof glass, while we know that is not true.

Just because the crew says something doesn't mean its true, look for the facts, Physics have more crediblity than some phony pilot trying to make an advertizment for a product.
Physically it is not possible what the pilot has claimed you know it, i know it everyone with a brain knows that.

Geronimo wrote:If this was true, then it would be forbidden to shoot the gun at high off bore but in reality the crews use the turreted gun at will, so it is obviously false.

This is one of those non-arguments i really hate when people don't know anything better to reply.

I heared such non-arguments dozen of times which were going like "M829A3 was designed to kill all tanks, so if it couldn't kill all tanks they wouldn't use it" sure that's why they are developing M829E4 and that all tanks were designed to withstand HEAT,RPGs,ATGMs,APFSDS has no value as long people see it convenient and suites their case.

This is nothing new to helicopters, Mi-24P when it first got its 30mm Gsch, it caused trouble, it caused even cracks to the frontal holding system and the virbation were transported to the fuselage and reduced the fuselages lifetime, this was later fixed by using reinforced rubber and a poofing zone between holding system of the cannons barrel and the fuselage connection to the gun.

Just because something makes trouble doesn't mean the military will let go it, hell even the F-35 which is least promising and so far a total failure for every single goal they gave to it is still alive and it doesn't function at all.

Werewolf wrote: the azimuth to the helicopter itself is not 90° but more like 20° which still has some stabilisation from the directional flight of the helicopter.

No. In the Afghanistan video, at the beginning of the gun run (2:26) the azimuth is close to 0°. Near the end of the gun run (2:41), the azimuth progressively shifts to the left and the pilot announces "Break right !" (2:46).[/quote]

Geronimo wrote:
Whether the crew is lying or not I don't know, but I have found the reference to this claim :

The gun is at its most accurate when fired pointing at 90 degrees to the fuselage and aimed slightly downwards.  The aiming system provides the range of the target and automatically compensates for the movement of the helicopter.

http://www.defencereviewasia.com/articles/137/French-helicopters-in-combat


The Automatic Flight Control System can manage the recoil of the weapon:

AFCS, consists of two redundant digital computers which control attitude hold, ...and gun firing compensation.

http://www.defence.gov.au/dmo/asd/air87/eurocopter.cfm

You do understand the problem in what this pilots said?

Fire Control System works regardless where the gun is facing but the advantage regardless of what helicopter it is are engagements with the autocannon into frontal sphere not to sides.

If the helicopter shoots to the sides, the FCS tries to compansate it as much as possible but the canon itself has no stabilisation from the flight direction of the plattform that would absorb much more effective the recoil of the gun when it would should to the frontal sphere, so this claim of the pilots can't be true.

RTN wrote:
The USSR reacted to the Apache AH 64A by designing the SA 19  Grison which can increase the effective range of defensive fire & react quickly enough to kill the AH 64A before it can complete it's anti missile engagement cycle. The SA 19 achieved this by combining 30mm SPAAG and missile system using a radar package similar to the SA 15 but armed with very high speed 2 staged tube launched missiles .

However, with the advent of the Apache AH 64D Longbow this threat from the SA 19 has been neutralized to a large extent. The AH 64D combined a mast mounted millimetric wave band search and engagement radar with the ‘fire-and-forget’ millimetric band active radar seekered equipped Hellfire variant. A passive precision radio-frequency interferometer was added to permit the system to sniff out the emissions of the SA-8, SA-13, SA-15 and SA-19 search radars. The Longbow Apache could remain behind cover, raising only the mast mounted sensor package to search for targets, only popping up for a few seconds to fire a salvo of Hellfires at a detected target

There is already a problem, the active MMW seeker in Hellfire missiles have a very low power supply and small radar anyway, which results in bad performance and are not useful beyond 4km range and that in "clean" environmental with low interference be it artificially or surfaces that are scattering radar waves and raising the sideslops and vehicles can be filtered out. Those tactics the US army tried to fullfill in Iraq to penetrate Iraqis echelon to get to the "SAMs" they already recieved hard beating from units that had no IADS network and no night capabilities like some shilkas without radars.

The crucial part for Helicopters being able and having even a slight chance and effective results against any SHORAD, they need not only a weapon that has a higher weapon and the important part is having an effective range that is bigger than your enemies SHORAD system maximum range, but you can equip a helicopter with 40-50km range missile that does not solve the problem that you need to determine the position of your target without getting either to close and therefor into weapon range of SHORAD, nor endangering your mission by alerting your enemy by irridating with radar the target. Ground targets have usually higher ECM and ECCM capabilities, which leaves Apache in a worse conditions in that situation.