Black powder machine gun in an airplane

So, you have found yourself in a situation where the city you manage has finished producing their first powered aircrafts, biplanes.

They aren't too good. They barely fly 140 km/h, so they're pretty slow too. But you need them in the air against enemy drake mounted warriors, who, luckily fly 60-70 km/h and have top speed only at around 90-100 km/h. Drake mounted warriors are not that dangerous in the air, only having 240 pound composite short bow and a dozen of arrows for aerial combat, but they're a bother, dropping primitive molotovs on the ground and naval targets of your allies, so you need to take them down a peg.

You don't have synchronization gears, so you had to go for "pusher" setting, placing your propeller behind your plane, leaving the front of the plane open for your gunner who sits in front of the pilot.

Now, you're already working on switching into smokeless powder, but the war was sudden and it was quite low on your priority list. In a month or so, you might be ready to start pumping out your first maxims with smokeless ammo. But you don't have a month or so, you need to offer your airforceless allies support now. You need a stopgap solution, before the enemy completely overwhelms your allies.

Your army has machine guns, but they're crank operated black powder ammunition machine guns. The ones you have are replicas of historical black powder machine guns of the second half of 19th century. Gatlings are too heavy for your aircraft, but there are other, lighter historical machine guns that you too have (for example things like coffee mill gun and Gardner gun, or other such guns).

Your problem is that the gun needs to be light enough for a light aircraft and gunner should be able to reload the gun with minimal adjustments to the gun itself. So, which black powder machine gun will you choose for this job? Or would perhaps using period rifles be preferable to those?

• Don't fancy being the pilot of one of these things, sitting behind something spitting out copious quantities of dense smoke... Nov 9 '19 at 15:03
• @StarfishPrime I mean, you're in an aircraft, not a car. It's not like there's a bunch of stuff to hit up there, so being blind for a few seconds isn't as dangerous as one would think. Nov 9 '19 at 15:13
• I don't understand why your ground-based machine guns cannot shoot down these drakes at much lower cost than developing and building aircraft. Any bombing-drakes low and slow enough to actually hit their target is well inside machine-gun range and a fairly easy target. If drakes sit thousands of feet in the air to remain alive, they won't hit anything worthwhile except by pure chance. Nov 9 '19 at 18:31
• I think it wouldn't be a big modification to add a magazine with spring to Gardner crank MG. Afaik, first prototype of Browning 1895 was test run on black powder ammunition and worked well and used ammunition belt to feed cartridges to weapon. Nov 9 '19 at 18:52
• @user535733 I do have limited amount of machine guns and ammo. Not so limited as in not being able to send any, but it's only good enough to defend a few more important position. Mobile aircrafts that can both pursue retreating drakes and harass them while they retreat are very useful tactical tool, even if that harassment isn't as effective as it would be with a better plane and better gun. Nov 9 '19 at 18:59

Assuming we do want an actual blackpowder weapon, the key criterion is relatively light weight. For that reason multi-barrel contraptions like the Gatling or Mitrailleuse are out; banks of a dozen shotguns even more so. You should pick a single-barrel, multi-shot device: either the the Puckle gun or the Agar gun. Both are primitive and have problems that would make for interesting plot complications:

The Puckle gun is not really a MG, just a supersized revolver with maybe a dozen balls in a cylinder. You might be able to reload entire spare cylinders, but reloading makes for windows of vulnerability, and each spare cylinder increases weight.

The Agar gun is a true MG, is quite lightweight, and has been used in CW for continuous fire until the barrel overheated---a lot of shots. The original required additional personnel to reload the cartridges into metal cups, but I suppose you could avoid this by carrying a lot of readily loaded cups, which are lightweight. The big problem is the feeding hopper---it works fine when the gun is on level ground, but maneuvering in the air could cause feeding jams, or even spill the cartridges right out of the hopper. So the drakes riders' tactic would be to force abrupt maneuvers on the biplanes, thus disabling the gun. :-)

• Why not gardner though? 1 barrel gardner is pretty lightweight too. Nov 10 '19 at 10:21
• I went for the very earliest models, in keeping with the millieu AW. And it's more fun for the plot IMO using such crude, imperfect devices. The Gardner is fine, but it is third gen at least, using cased cartridges. But you are right in that it solves the hopper problem. Nov 10 '19 at 11:31

Use Shotguns

What exactly does a Gatling Gun do? It spits out a lot of bullets quickly. Why do you want to spit out a lot of bullets quickly? Because hitting a fast moving target is hard and if you fire a lot of bullets the chances of one hitting increase. So your real goal is to crate a hail of projectiles. Why not use a gun which can create such a hail with a single shot?

The ideal setup in my opinion would be to have the gunner sit behind the pilot and construct his seat in a manner allowing him to shoot downwards. He has a rack with about ten double barrelled shotguns in front of him, so he can fire a decent number of shots in quick succession.

The strategy to fight dragons would either be to fly very close to them and kill the rider or the dragons wings with a barrage of grapeshot before he can snipe you or to gain an altitude advantage over the dragon rider and use the gravity-extended range of the shotguns to kill the dragon rider in a hail of shotgun fire. After each attack run the gunner would have to reload the shotguns for the next one. Story wise these two strategies could create some interesting conflict between two schools of thought in the military. Young, heroic, showoffy plane crews preferring the dangerous, but quick "meele" while the leadership prefers the saver, but not always successful altitude strategy.

This shotgun setup has the advantages that the gunner would have a very wide firing field compared to a front mounted gun, the smoke would not borther the pilot as the gunner sits behind him and the armaments of the planes would be a lot cheaper, which is always nice.

EDIT1: I do agree with user535733 assessment that you can find better uses for your aircrafts than fighting dragons. The shotgun setup would just be an easy and nice addition enabling aerial combat. The "gunner" could do other useful stuff like observation or communication whenever he is not fighting.

EDIT2: The issue of range was raised by some people, but I think they misinterpret the situation and rely too much on plane VS plane dogfights. Buckshot is still somewhat useful against human sized targets at about 100 m, but even if this is truely the limit, one must remember that we are fighting drake, not airplanes. Firstly the drakes will have large, woundable wings instead of hard, armored scales and those will probably be about an order of magnitude bigger than human sized. Secondly the altitude strategy will greatly increase the effective range of shotguns. Thirdly, if airborne fights between birds are any indication, the drakes will attempt to ram the plane and take it out in meele. This is really their best bet. A front-mounted machine gun will do jack shit against a drake attacking from above. A shotgun will discourage any tackling attempts.

In a different note, I thought about using time fused shotgun shells, aka flag-granates, against the drakes. The technology is ancient, the Venitians invented time fused artillery shells in the 14th century. I'm not sure at which point in time handgun sized time fused shells for granate launchers became a thing, but I'd be willing to suspend my disbelief if OP uses them. They would definitely sort out any range issues, be useful for precision close air support and if they can be fired from the same guns as the buckshot they'll give the airplane a versitile arsenal.

• Thank you, that's a really interesting idea with shotguns, although I'll have to check how bad will the air restitance impact the shots, but I have to say your idea looks very promising, since injuring the wings is more than enough, and I think the shots might have potential to cause wing injury even from a greater than a short distance. Nov 9 '19 at 18:36
• Why machine gun and not shot gun? Range and piercing capability. A shot is small, round and has a much higher drag to weight ratio than a normal bullet, the later of which is typically shaped for low air resistance. So the shot looses the little energy it has much quicker, making it simply bounce off the thick drake hide, if it reaches its target. And air fights are typically long range fights: Even at 90km/h each drake/plane covers 25 meters per second. You can't get much closer than 100 meters before you have to turn away to avoid crashing into your target. A shotgun is worthless on a plane. Nov 9 '19 at 23:39
• @cmaster The shotgun doesn't need to shot birdshot/buckshot, it could also shoot something like a cluster of flechettes which are much more aerodynamic Nov 10 '19 at 9:59
• @Dragongeek Flechettes sound like a great idea. The technology is definitely old enough, after all, the first cannons used flechetts. Nov 10 '19 at 11:13
• @cmaster Adressed your points in EDIT2. Nov 10 '19 at 11:15

Just do the same as the drakes, you're more effective.

Assuming that there's a reason other than the plot demands it for the meager amount of arrows and other equipment on the drakes that lends itself for aerial combat; you can just copy them.

Your biplanes should be strong enough to easily carry two people - even if that means their top-speed drops closer to the drakes. Carry a dedicated gunner or even bow-person that does the shooting, and even drops molotovs or nets on the drakes.

You really don't need any fancy machine guns to hit targets that you can match speeds. Especially at such slow speeds. Shooting a bow at about 3.5 times the speed of your drakes, or a bullet at 9-10 times the speed of them, your planes shouldn't have that hard a time harassing the drake-riders enough that they become useless.

Not knowing what exactly you mean by a 240 pound composite shortbow, I'll take the speeds advertised for modern compound bows, which seem to be around 50-70lbs of draw-weight. Assuming your 240 pounds to be the draw weight of your fantasy bows, I guess the calculated speeds for bows with 1/4th of that are at least not too high. Thus we get around 300-340 feet per second arrow-speed. Or a rounded 100 meters per second -> which neatly translates to 340 km/h.

The muzzle velocity for blackpowder guns seems to be somewhere between 120 m/s to 370 m/s according to wikipedia. Taking the mean of these to values so we don't have to think about air resistance, etc. we end up with about 250m/s -> some 900 km/h.

• That 240 lb draw bow is magical shenenigans, but your arrow speed shouldn't be too far off. Compounds are just way more effective, and I imagine the best we could get in this case from my bow might be 20-30% more speed. What I was hoping for was a way to harass drake riders from beyond their range. I assumed that machine guns, even blackpowdered one, with their decent accuracy and decent rate of fire are good for it. If I has semi-auto rifle, that might be good too, but I don't. My rifles take good few seconds loading on the ground, and doing that mid air seemed bad. Thus I thought MGs. Nov 9 '19 at 19:30
• But I might be wrong and ordinary rifle might be good enough. Or as recommended above, shotguns seem nice too. Nov 9 '19 at 19:31
• @FailusMaximus There are two advantages of machine guns over non-automatic guns on planes: 1. Accuracy. When a single bullet may go off the mark, an MGs bullets center on the mark, making sure that some hit close enough. 2. Motion. When you shoot at a plane/drake that's not directly in front of you, you cannot aim at the plane/drake itself. You must aim at the spot where the plane/drake will be when the bullet hits, and there's no good aim guide to do that. With an MG, you just fire a stream of bullets in front of the target and rely on the target to fly through that stream. Nov 9 '19 at 23:53
• @cmaster Shotguns work fine against birds, I think they'll work against drakes or their riders as well. Nov 10 '19 at 5:18
• @Ryan_L They work fine against small, lightweight animals at relatively close range. It's a big difference whether you are trying to shoot down a 3kg bird, or a 300kg ridable steed. And due to the speed of the combatants, air fight weapons need longer range than a typical shotgun offers. You don't care so much about the later as long as you are shooting arrows down as gravity will assist you. But if you are trying to hit something 200m away on the same level as you, you want a fast bullet that doesn't loose significant amounts of speed while it's on the way. Nov 10 '19 at 8:24

Your initial aircraft have much greater value as scouts, observers, and secure messengers than as active combatants. Skip the hassle of the gun entirely until your smokeless powder is ready.

Survival is about speed and maneuverability: Your aircraft is faster than a drake, and should be able to break contact at need. As anti-air combatants, your craft should by lure enemy drakes into pre-arranged ambushes from ground unit fire instead of directly trying to shoot them down.

Once you have sturdier, faster, more maneuverable aircraft, smokeless powder, and synchronizing gears, your battle in the air will evolve to become very different. But you're not there yet.

• The drake riders can't basically fight back at all. Would be pity to not just take a shot when they can't really return fire. My aircraft is good enough to cause something akin to Fokker scourge. Nov 9 '19 at 17:58
• Your question did not state that the primary purpose of your aircraft is a weapon that shoots down drakes (indeed, it didn't give any purpose at all). If true, that's an important omission from the question. Also, your statement that "They aren't too good" seems important. There are lots of noncombat tasks that have strategic value to win the war that an early biplane can do. For example, scouting out the drake feeding and nesting grounds, so your land forces can ravage them. Nov 9 '19 at 18:13
• Instead of bullets, think about dragging long tails of razor-wire over drakes. An injured drake that flies home takes lots of enemy resources to tend and heal. You want drakes to learn to fear the sound of aircraft engines. You can use that against them later. Nov 9 '19 at 18:18
• I am sorry for being confusing, I thout my "You need a stopgap solution, before the enemy completely overwhelms your allies." Was good enough. I'll try to reformat the question so that important parts stand out. As for wires, that requires too close of an approach. While archer seated on the drake only has a bow, they're still elite archers so if you approach the drake too close, they might hit you. I chose machine gun as my stopgap solution, because it allows aircraft to attempt to take enemy down without too close of an approach. Nov 9 '19 at 18:26
• Since you want aircraft-machine-gun based solutions, you must clearly, explicitly say so in the Question, lest folks waste their time giving you solutions that you don't want. Nov 9 '19 at 18:28

It depends a bit on the exact vulnerabilities of the target but assuming they had bat-like wings I think a large shot gun would be quite effective At spoiling their aerodynamics and ruining their ability to fly.

Since it doesn’t have to be carried by human you can use something like a “punt gun” which is more akin to a small cannon than a normal shot gun.

Much depends on the relative agility of drakes and planes. If the planes are better, I would stick with a prop on the front of the plane and have a punt gunner with a swivel mount on the back. Flying alongside and blast 'em.

I suspect drakes might be more agile though, in which case your planes are doomed. Their riders' weapons are useless, but all it needs to do is rake the wings to send your plane plummeting to their certain destruction.