Could you design a fighter plane for a centaur?

Question

It's the Great War, and all the nations are having a good time of it, painting their biplanes flashy colours, as they shoot into their own propellers!

But over in the corner, lonesome and dejected, the centaur nations had no planes at all.... They can't fly anywhere, they don't get to put on goggles or get set on fire while simultaneously suffocating. They just sit sadly in the corner. As they get ready to charge tanks with lances, they pause to stare up, wistfully, at the thunderous air-battle between knights of the sky.

That was... until YOU came along to make them a fighter plane!

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Could a centaur nation, with WW1 tech build a fighter plane which a centaur could pilot? If that's too much to ask, you can reach into WW2 levels of tech.

So, there are a few points to consider.

1. Can you build a fighter plane for a centaur?
2. Would it have any unique characteristics, compared to human fighter planes?
3. Would there be any advantages or drawbacks to centaur pilots compared to human ones?

I've written an example answer, if the metrics are unclear (since I have been badgered extensively about strange metrics, of late).

Answer 1

You definitely could. However, I have thought of a few additional concerns:

How do you strap in?: Human pilots preferentially sit in a chair, and can easily be belted in. How do you strap in a centaur? Do they have to straddle some kind of saddle, and then tie in straps over their back? Can they strap themselves in, or do they need someone else to do so?

Plane Control: Human pilots use their feet to control the rudder. If a centaur is standing, they cannot use their feet in such a manner. If strapped in properly, they potentially have 4 feet to control with, or 2 more than a human pilot. This allows another axis of control - perhaps they can fly with just their legs, and use their arms for a gunner control?

G forces: You mention that they may be better at handling G forces, and that is a possibility, but G forces will have a very different effect on a centaur as opposed to a human. Think of a tight upwards loop - the human pilot is in a nice reclining position, and most of their blood stays in place. For a centaur, this same maneuver would cause all of the blood to pool in the "horse portion", resulting in a complete blackout at a much lower G force.

Answer 2

Yes, it would be possible to build a plane that a centaur could fly using WWI technology, but the centaurs would still be at a severe disadvantage because they would need to build very big and non-maneuverable planes to accommodate their larger and heavier bodies.

Now, WWI was the first war where actual air-battles took place and where aircraft played a major role. Before WWI, the only aircraft that militaries employed were observation balloons, the occasional zeppelin/blimp, and a handful of spotter's planes. Powered aerodynamic flight was still in its infancy--in fact, at the beginning of WWI, air-battles were so primitive that they consisted of pilots flying around in their planes with a pistol in one hand and the plane's yoke in the other, trying to shoot the other pilots or a critical component of their extremely lightweight aircraft.

For example, one of the most famous planes in WWI, the German Fokker Eindecker massed in at 400kg empty and 610kg full. This plane had one pilot and an integrated, propeller-synchronized, machine gun along with a flight time of roughly 1.5 hours. Comparably a single horse can easily mass in anywhere between 450-1000kg, which is heavier than that plane, pilot, ammunition, and fuel combined. A scaled-up plane would work from an engineering perspective but would require longer runways, more materials, and be more expensive.

In my opinion, for centaurs, plane technology simply isn't advanced enough in WWI to make building fighters worthwhile unless there are Shetland-centaurs or they're willing to train child-soldiers into being pilots--if they need planes, their fighter-equivalent would be the size of a human's bomber.

Still, that doesn't mean that the centaurs can't take to the skies. If they instead focus on high-altitude zeppelins, blimps, and balloons, they may be able to play to their advantages against humans or humanoid races:

• Centaurs have a much higher lung capacity than humans. This means that they can operate at higher altitudes without requiring compressed air tanks.

• Centaurs are naturally more equipped for dealing with the cold. A centaur has the thermal mass along with the fur to withstand the cold temperatures at high altitudes easier than a human--no matter in how many layers they bundle up.

• Centaurs have more natural strength compared to a human. Normally, this doesn't matter as an airplane can't be powered by 1hp, but an already buoyant blimp could be powered by a centaur-bicycle system.

• Centaurs have more limbs than humans. Although it would probably require training, a single centaur could probably pilot a plane with their hooves while manning a gun with their hands.

Answer 3

They actually existed

Below is a picture and specifications of a Centaur 2A, built in 1919. The photo doesn't show the centaur pilot. I'll see if I can find one. Edit - Found! diagram added at end

Note that the centaur's head and shoulders stuck out of the fuselage where you can see a dip near the front in the picture. It would look like an ordinary pilot was flying. The horse body was totally concealed within the fuselage. It was tricky to get in. I'll see if I can find a picture of that. There won't be any videos from the time.

Answer 4

Why would you need an engine when the pilot is an engine with a peak power of about 15 hp?

Thats right. Although we call it horsepower, a horse has about 15 hp (peak performance).

So going into another direction than retrofitting a plane which was designed for weak humans, we could design a plane that uses the centaurs muscle energy to create lift. I'm thinking about a glider with a bike-like mechanism to power a prop. Considering that your centaurs might be technologically behind other races, that would fit well.

There is also the advantage that you don't have to build a complex engine for each plane. You just need some wings and gears. Centaurs would have a huge numerical advantage.

Answer 5

Don't let the neighsayers and badgers keep you from your dreams of flight. Have you ever thought about a...

Flintstones Plane

You read that right. I attached a picture of the Flintstones car above for reference, should you happen to not have watched that cartoon before.

My proposal is for the bottom of the plane to have four portholes for the centaurs to stick their legs out of. I'm leaning on the trope of centaurs being faster runners with much more stamina. The idea is that the centaur can use its leg power to perform a kind of assisted takeoff with reduced ground run distance required, or conversely use its legs to help bleed off speed when landing and come to a shorter stop.

Considering the burden of additional weight a centaur would place on an aircraft from the 1910s, this might be needed to break even with a non-centaur plane and not actually be a comparative advantage.

Answer 6

Starting from point 3

As far as I can work out, there'd no benefit to having a centaur pilot as opposed to a human one. Their physical strength and speed are no advantage to them, but rather are detriments.

But... then again

Though... maybe you could extrapolate some advantage in that centaurs/horses have larger lungs and bigger hearts (and possibly two hearts), and so might handle G forces and high altitudes better?

They would have an easier time staying warmer, being a larger creature with some fur. So, thinner pilot jacket, less discomfort and clothing to handle the cold. That would only be a minor benefit.

Cultural benefit

Hunters had good records as pilots, with many of the flying aces having been hunters. So the culture of hunting and marksmanship associated with centaurs might make them better shots and fighters on average... if their plane is still manoeuvrable enough that they had a fighting chance, that is.

Regardless of their effectiveness, I imagine national pride would lead to experimental centaur fighters, who may be used in a war. If their results were good, they might make more.

Plane Characteristics

Let's move onto how the plane characteristics might be effected.

Size and weight

A centaur is long, tall, and heavy. Maybe they can lean forward, the equivalent of a horse reaching its neck forward, to reduce their height... but that does increase the length issue.

This could necessitate a larger plane. Though if you removed the copilot, they might fit into the plane by lying down, and it wouldn't need to be much bigger? That could be helpful, so that it's a fighter plane instead of a small bomber.

Parachutes

It may not be practical to give centaurs parachutes, since quickly exiting the craft and the expense of producing such a large parachute may be prohibitive. On the bright side, parachutes weren't that common through WW1. Planes were flying low enough that it was a dubious proposition for a fighter pilot.

I do wonder if you could produce parachutes for centaurs at that point in history.

Plane Characteristics

Those things together, the plane might have a very large passenger compartment, filling the position of the pilot and copilot. Anything important in the plane between those points will have to be moved elsewhere, which may mean a larger plane. If the added weight of a centaur (anything from 900lbs to 2,000lbs) was an issue, they might need a more powerful engine, which could make the plane a fuel guzzler.

If those things are true, then a larger, heavier plane with more powerful engines could make for a unique fighter design. You might even exaggerate it by adding additional armour or engines? Potentially, it could be that centaurs don't build pure fighters, but instead building something more like a fighter-bomber.

Tactics

If you can make an air-doctrine which can emphasize the strengths of greater armour, power, and maybe firepower, then this could help subvert the weaknesses of the centaur. They probably have a history of Mongol-style tactics, so they might be skilled at bombing runs or even feigned retreats.

With more powerful engines, you may be able to outrun enemy fighters, although mobility is likely not great, compared to the Steppe ponies of the Mongols. You may have to compare them more to the heavy horse charge of knights, where in this case instead of lances they would use M2 Browning .50 Calibre machine guns, with a heavy enough plane and pilot that you DON'T want to be playing chicken when they dive in your direction.

Can you build it?

I can only guess at this, as I lack the data to approximate how difficult an extra half ton of weight is for WW1 planes. But, towards the end of the Great war... I think it's possible. By WW2, you certainly have fighter-bombers, and they were being developed at the end of the war.

Answer 7

I want to highlight the opposite approach to IronEagle rather than leave it as a comment.

The safest posture for your Centaurs in a plan is to be laying down. This avoids having to stand when pulling Gs providing the same benefit as sitting for a human pilot.

This does obviously mean they'll be restricted to hand controls only. So your Centaur is going to have to cope with doing different things with each hand to give them the extra control interface that a human pilot gets from their feet. Similar to the way a Helicopter pilot has an extra plane to control by hand (assuming I understand Helicopter controls, which is not a given).

A horse weighs roughly 8 times what a human does, so you'd have more difficulty with older planes where weight was a major issue.

The next problem as you move towards more modern planes is ejector mechanisms. You don't want your Centaurs to have to ride their craft down in a blaze of glory each time there's a problem, so replacing the functions of the ejector seat in a modern fighter or the "bail over the side" strategy of an older model will need some consideration. How does a Centaur use a parachute?

Answer 8

Being half-humans, centaurs really can drive planes: arms for the steering wheel, front legs for the pedals. And as you mentioned, there is an additional benefit having two more legs so they can be used for something good (extra flight controls, actuation of machineguns and cannons...).

Counter-side: horses are 3-5 times heavier thus we need more "horse power" at the engine. Also, it's harder to board/unboard a pilot to the plane (via belly-mounted ramp? or via a crane device?). Finally, having a bigger body, the pilot is more exposed for being wounded by the enemy fire.

All after all, centaurs are more likely to be bomber pilots, or any other essentially big planes where a pilot weight is not that noticeable compared with entire "takeoff weight".

Answer 9

A lot has been covered in other answers, so I just want to add two specific points to consider:

1. Because centaurs are so much more massive, it will take a few years longer to develop the first planes that can carry them as pilots. A centaur-only world wouldn't invent planes as soon because it's a harder problem for bigger passengers and pilots.
2. I think it would be harder, not easier, for them to handle G-forces. Because they are much more massive, the square-cube law makes them generally more fragile under their own weight. Also, they would need a cradle supporting their ribcage, and more of their weight would be pressing down on their lungs. This would become more of an issue as they entered the jet fighter era, and eventually it might be enough to keep them from being competitive as fighter pilots.

Edit added to emphasize the square-cube law: Muscle and bone strength is proportional to cross-sectional area. Centaurs would be strong because their muscles and bones would be larger, with greater cross-sectional area. However, the volume and mass grows faster than the cross section. If you double the dimensions of a cube, it has four times the cross-sectional area and eight times the volume. This means that centaurs would be weaker in terms of fighting Gs, because the weight pressing on their ribs would be larger per unit cross sectional area.

However, you could always put in a fantasy element and assume they are made of inherently stronger materials. Maybe even give it a semi-scientific rationalization.

Answer 10

It (joke aside (yet not too far)) may have looked like this, allowing the centaur to step in and out easily.

More seriously, as mentioned in other answers, centaur must have comfortable position allowing to withstand g forces, something like this could take place inside the cockpit:

(source)

Answer 11

Lung capacity of a centaur might help in doing strenuous work at altitude, but there are two biophysical limits that cannot be overcome by just increasing lung capacity.

Lungs are basically a semi-permeable membrane that allows gases to pass through. Oxygen moves from air to blood because the partial pressure of oxygen (ppO2) dissolved in the blood in the lungs is lower than ppO2 of the air in the lungs. Carbon dioxide moves the opposite way because its partial pressure (ppCO2) is higher in the blood than in the air, because the blood brings more CO2 into the lungs all the time. But there is nothing to stop the gas exchange from going the other way if the partial pressures change, or to force it to happen if there is no sufficient difference of partial pressures.

There's also some water vapor, which always stays at or above certain minimum partial pressure (ppH2O) by the physiology of the lungs: if the air you breathe is drier than that, some water will come out of your blood and so you'll lose moisture on every exhalation.

And finally, there's the partial pressure of nitrogen (ppN2), which is important for scuba diving, but in aviation it basically just takes up space from the important gases (unless you're flying soon after scuba diving, in which case you'll need to be careful).

As altitude increases, the ambient air pressure decreases, and the partial pressures of the various components of the ambient air decrease in the same ratio. But in your lungs, the carbon dioxide and water vapor exiting the blood will keep the partial pressures of these components of air at or above a certain minimum level. Basically, when you reach the point where the sum of partial pressures of ambient nitrogen + carbon dioxide in the lungs + water vapor in the lungs equals the total pressure of ambient air, the flow of oxygen from air to blood will be completely blocked. You can breathe all you want, but you aren't getting any oxygen in.

If there is any remaining oxygen in the blood, it will actually escape if the ppO2 in the air is lower than the ppO2 in the blood. This a big part of the reason why a sudden depressurization in a pressurized aircraft at altitude makes you pass out so quickly, and also why the safety instructions in passenger airplanes tell you to always put on your own oxygen mask first before helping others.

(This is why mountain climbers talk about the "death zone" near the peak of Mount Everest and other tallest mountains: if you are near the top of Mount Everest and not using supplementary oxygen, you will be effectively suffering from a constant oxygen shortage because you're approaching this limit.)

By using supplementary oxygen at ambient pressure, you'll effectively replace the useless nitrogen component with more oxygen, which will allow you to go higher.

But once you go high enough, the sum of partial pressures of just the carbon dioxide and water vapor in the lungs (which have a minimum limit set by physiology) will equal the total pressure of the ambient air at altitude, and then you'll have the same problem again, and supplementary oxygen will no longer help. At that point, you will need either a pressurized cockpit, or a spacesuit.

(Source: an aeromedical lesson that was part of glider pilot basic training.)

Answer 12

Why not use some other sylvan race as pilots? Centaurs usually live in sylvan forests, close to pixies and suchlike. Among them should be ideal candidates for flight.

Centaurs can be ground personnel where their strength and speed will really shine. Imagine mechanics with a built in 15 HP engine for moving equipment.

Some ideas: find some warlike tiny woodland creatures for use as pilots. Think Nac-mac-feegle or D&D blood-caps. They don't need to fully understand aviation, just enough to be able to fly. Races like pixies that have wings would be ideal. Centaurs can do the engineering and everything, so the pilots don't need to be able to advance tech.

Imagine the centaurs seeking out the remnants of the bloodcap tribes, trying to get them to drive the planes. With both groups being at different points of civilization, and perhaps even intelligence!

The human "pilot ace is the hero" culture don't have to appear, after all. There might be a more collectivist feel to it, with each team of pilot(s) for the plane and controllers/tacticians sharing name and fame.

Answer 13

Alas, not in 1918. But for WWII they'd take Flying Fortress to a whole new level

So there's been some great answers here, but few seem to truly appreciate the fact that flight was NEW in WWI, and subsequently the aircraft were not great. Planes were so primitive that nobody actually knew what they were doing, even in 1918. To the point where there were no wind tunnels, and nobody would be quite sure if design would even fly until they built a full-size model and tried it. For another example, seatbelts were very specifically not a thing in WWI aircraft. Why? Because the odds of the plane catching fire (accidentally or through enemy action) were HIGHER than a pilot being thrown out of the aircraft. So in case of a crash, the 4 seconds it takes to undo a seatbelt could mean you were still in the wreck when it caught fire/blew up. So your centaur probably wouldn't bother with a seatbelt either, because plummeting to one's death is infinitely preferable to burning alive.

The one advantage I can see for a centaur, larger lungs and body = better in the cold and at altitude, is not super useful in WWI aircraft. Because of the limitations of the planes themselves, climbing high enough for the centaur to put its advantages to use wasn't really a thing for most of the war. Even when planes COULD achieve that height, they didn't really know what they were doing. By that I mean "oil would freeze, guns would freeze, and generally the damn things wouldn't work because people didn't quite grasp all the ways that 10,000+ft was different than ground level!"

The power to weight ratio of even the human-crewed WWI aircraft was laughable. As already pointed out most of the fighters fully loaded weighed less than your average horse. So even if you handwaved "my plane can go high enough to give a centaur the advantage in cold/oxygen" you've increased the carrying capacity of your plane such that a human pilot could throw in an oxygen tank and/or enclosed cockpit. The power-to-weight on a WWI plane was no joke. They didn't carry parachutes as standard. For the brit's, it was because they were afraid pilots would bail out instead of saving the aircraft. But for LITERALLY ALL THE OTHER NATIONS AT WAR it was allowed, and pilots still wouldn't do it. The reason most pilots wouldn't carry parachutes is because the 10kg that parachute weighed was better spent on ammo, speed, climb, or maneuverability. Unlike in WWII, where a few extra pounds was NBD, in WWI it was the difference between life and death.

By WWII the science of aircraft and engine design had advanced enough that you could have centaur-piloted aircraft. But power-to-weight is still something of a problem. Centaurs would be at a supreme disadvantage in fighter design, as their craft would be necessity be bigger, less well armored, less maneuverable and likely slower than their human opponents. However given their engineering needs (have a useful aircraft with 1 or more 500+kg crewcentaurs) I think they would be VERY heavily invested in bomber aircraft. Something like a suped-up B-17 would likely be the order of the day. A big long-range heavy bomber can more easily accommodate horse-crew. They'd have to be well-trained though, as you'd need to economize crew to save weight. (For example, no copilot and merge the bombardier/navigator position, because each centaur means 1 fewer 500kg bomb carried) They'd also, due to the limitations of centaur fighter support, likely take the idea of a "Flying Fortress" to extremes unseen by human bombers. Because you can't rely on fighter escort and need to keep crew to a minimum, perhaps their bombers would forgo machinegun turrets for light flak cannon or other more dangerous weapons. They'd likely not work super well (humans after all were wildly over-confident in the ability of bombers to "always get through" the B-17 was originally envisioned to need 0 fighter cover and look how that turned out.) but perhaps some other tech innovations like proximity fuses making their bomber-born flack cannon wildly more deadly than humans would expect could give them an edge.

Or maybe their quest for MORE POWER to lift their extra-large crew means they take a gamble on jet engines more readily than human nations did. So something like the British Meteor (slowed down due to budget and reliance on old-but-proven propeller-aircraft tech) gets invented by centaurs first and they have it by 1939. That'd give them the power to create fighters capable of going up against prop human aircraft. or just big strategic bombers that went fast enough they'd be untouchable by human prop-planes. The advantage would be fleeting, because when humans saw what they were doing they'd swarm over it much like how the allies reacted to the ME-262. But it'd be a fun narrative to dive in to.

For more fun Great War aviation facts, I suggest "Marked for Death" by James Hamilton-Patterson and "Gunning for the Red Baron" by Leon Bennett. Be advised that, like all books on WWI, they get REAL depressing at points.

Answer 14

Consider if the Centaur-flying inspiration might go in a very different direction than biplanes. They're already most of the way towards having the form of a Pegasus, anyway (which perhaps also exists in the world with other fantasy races such as Centaurs?).

Instead of looking at the Centaur body as a handicap, instead see how it might be an advantage; the Centaur's long, extended, powerful body serves as a ready-made fuselage. Perhaps Centaurs are happy to have mostly glider-equipped forces. This could dispose of the usual seat that humans need, and instead just strap a set of wings to their back. Perhaps the primary usage would be as drop-troops, such that Centaurs could silently land behind enemy lines and then leverage their powerful charging ability on land to disrupt enemy forces.

Alternatively, we could go back to the start of real-world air flight when human-powered flapping-winged aircraft were the subject of experiments. While these didn't work, perhaps Centaurs with their powerful legs could have made this successful (again, with no need for a seating mechanism, but instead with faux-pegasus wings strapped to their back).

Video at YouTube

Answer 15

I don't know how much centaurs weigh, so I just did all of the following using a hypothetical "average horse". I think it's funnier to think of horses flying planes anyway.

So, just thought I would add some numbers to spruce things up. The common German fighter during WWI was the Albatros. It's empty take-off weight was 659kg and its maximum take-off weight was 886. A horse often weighs somewhere in the order of 450kg (about 1000 lbs). (659 + 450 = 1109 > 886). A centaur would not be a good fit for that plane.

But let's change our assumptions. Say our friendly centaur has access to the best engine at the time. While the average plane was powered by a 160hp, rotary engine, by the end of the war engines had improved to get up to 400hp. So, more than twice as nice, yes?

Well, let's take a look. If a 75kg (165lb) man (without any equipment) had 160hp, then he would go about 9.6 km/minute. With 400hp, this number goes up to 24km/minute. What about the horse though? A horse weighs about 6 times as much as a man. This means that the horse, even at some of the best engines at the time, would only get 4km/minute.

Hm. That's not looking good. But I'm doing those calculations without accounting for the weight of the equipment. What happens if we include the weight of the plane? A mostly-empty Albatross, with pilot, using the best engine at the time, can do roughly 2.5 km/minute. The horse would go about 1.6 km/minute.

So clearly, we're better off using humans in the skies, but what if we gave a human an old plane and the horse a new one? Well, then you're talking about the human in the 160hp plane getting to just under 1 km/minute with the horse going 1.6. If we limit the human to the engines common immediately before the start of the war (80hp), the human would go less than a third the speed of the horse. Seems like the horses might have a fighting chance.

So, if you can solve for the extra strain on the structure of the plane and provide the horses with technology roughly four to five years ahead of humans, then it seems entirely possible for horses to win dog-fights.

What about g-force? Well, g-force is a question of maneuverability and acceleration. A 400hp engine accelerating as fast as it could with a horse would not accelerate as fast as a human pilot, even if the horse were accelerating twice as fast. As for maneuverability, that follows the same rules. The heavier the payload the slower it can turn and, consequentially, the less g-force the pilot will experience.

Answer 16

I am just "putting my two cents in" here:

But do you know the actor Fess Parker of the good old times tv show Daniel Boone (one of my favorite tv shows ever) was turned down by USAAF because he was too tall at 6 feet 6 inches (1.98 m)?

https://en.wikipedia.org/wiki/Fess_Parker

He enlisted in the U.S. Navy in the latter part of World War II,[6][7] hoping to become a pilot. He was turned down because he was too tall at 6 feet 6 inches (1.98 m).

In deed, Apollo project astronauts had a very strict height limitation. Not too short, not too taller.

Believe me, the airplane engineers are great, but place a 2143.38 pounds, four legs plus two arms man/animal inside a cockpit is out of question in Word War One, Word War Two and Word War Three!

Answer 17

Ornithopter.

The half-horse features would provide an average of 1HP(746). Far higher than a cyclist that gives 300w. That means you can make them excellent Commandoes!

Propelling silent ornithopters that move in the night, deadly ambushes behind enemy lines!

Answer 18

"It's the Great War, and all the nations are having a good time of it, painting their biplanes flashy colours, as they shoot into their own propellers!

But over in the corner, lonesome and dejected, the centaur nations had no planes at all.... They can't fly anywhere, they don't get to put on goggles or get set on fire while simultaneously suffocating. They just sit sadly in the corner. As they get ready to charge tanks with lances, they pause to stare up, wistfully, at the thunderous air-battle between knights of the sky."

Why on Earth would the centaurs want to "get set on fire while simultaneously suffocating?" The problem here is you're taking centaurs away from their natural role and making things really, really complicated! See, centaurs are essentially cavalry, for all intents and purposes. Additionally, if centaurs so much as exist, one of two things must be happening:

1. Science-Someone has the tech necessary to create chimeras (creatures that incorporate cells from different species, AKA sphinxes, mermaids, centaurs, lamia, and so forth) and is doing so over and over (chimeras can't breed another one of their kind)

2. Magic-either someone used magic to combine animal and human parts to make that centaur, or someone used magic to combine a human and horse to make that centaur.

I'm assuming magic, as otherwise a centaur nation is almost completely impossible (come on, how likely is it that an entire nation of genetically engineering chimeras exists and is being maintained by a veritable army of mad scientists?), and so the centaurs should, naturally, have magical enhancements.

These enhancements likely concern strength, endurance, and speed and everything that would make life difficult for a centaur would likely have been accounted for. Additionally, if these centaurs are anywhere near as fast as the ones in the Percy Jackson series, they can easily take down a tank with the right equipment.

Tank treads are really quite vulnerable; not the entire thing, mind you, but the track pins and gears are relatively unprotected, especially back in WW1 (which is what this sounds like). Quickly placed or thrown mines, anti-tank guns, cannons, or even a thick tree trunk stuck in the treads should break the thing and render the tank useless. A lance of the right material (mithril maybe? This is fantasy, right?) can just penetrate the armor and kill the pilots.

In conclusion, centaurs have no reason to build planes as they'd be much more effective as "infantry" and can very well develop anti-tank and anti-plane weaponry to make up for the lack of either.