Why don't they make hybrid jet/propeller fighter jets?

thrust vectoring rules the skies

Because that's ridiculously complicated

>>32413583
what's the biggest obstacle

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First of all, it's actually been tried before and didn't go so well.

WWII planes turned well because they were small and light compared to modern ones. Taking a modern plane and adding a prop would just add size and weight, and make them even worse. You'd lose performance in both modes because they'd have to drag around the extra weight of whichever engine wasn't currently being used.

>>32413598
Needing multiple fuel lines, propellers effecting aerodynamics, reliability, ETC

>>32413611
what if it was a fighter drone to cut weight and balance out the propeller

>>32413613
>propellers effecting aerodynamics

What if they were conformal + retractable

>>32413635
*as in like an eyelid type cover

>>32413548
I don't give a fuck about your stupid thread, but I want to say that the Super Constellation is the sexiest aircraft ever built

>>32413660
maybe you find it sexy because it's shaped like a BBC

>>32413598
You don't seem to understand how complicated a system you're proposing.

As they stand, modern propellers are complicated pieces of equipment, requiring special gearing to vary the pitch of the propeller to optimize for the flight speed, as well as gearboxes between the turbine driving it. Retracting a propeller now creates several new points that must be designed, as you're not just folding the propellers down, but disengaging the driveshaft, stopping the prop from spinning, and most likely deploying some kind of cover for the retracted blades.

And all this will be for negligible benefit. The only benefit of a prop-driven aircraft is greater efficiency at very low speeds - Mach 0.5 and below. Meanwhile, most jet aircraft operate at speeds of around Mach 0.8 to 0.9. You'd have moderately better efficiency at very low speeds, but the aircraft's almost never operating at those speeds, so it's not worth the effort. There is the niche that propellers tend to be quicker accelerating than a turbine (as you can just quickly adjust the prop pitch instead of waiting for the turbine to spin faster), but again, this benefit is moot at the high speeds that modern jets operate at.

>>32413673
But wouldn't it be good if you could fire a missile at mach 1 and then be cranking at 170 knots?

If you wanted some sort of hybrid, a ducted fan driven by a small turboshaft would work.

>>32413692
No. There's no advantage to flying that slow in a combat aircraft, and, even if you're looking from the perspective of range, combat aircraft are designed for cruise at high subsonic speeds in mind, meaning that, when flying slower than that design speed, they're a far shorter range.

>>32413627
It's pointless, the only advantage props have over jets at low speed is fuel efficiency, and you lose that by carrying a second engine. Props don't actually make you turn better or anything, it was the rest of the plane that made the difference.

Modern jets can often outhandle WWII prop fighters at similar speeds anyway, especially if they have thrust vectoring or other trickery. The only place they tend to lose is in sustained turns but those aren't really relevant in modern fighter combat. (And it's hard to compare, because stats for modern jet turn performance are usually given at much higher speeds than classic props.)

>>32413713
But range isn't the point when you've encountered an enemy aircraft. I was wondering if you could have normal jet efficiency when moving into a target area then switch to propeller for dogfighting or cranking

>>32413728
Nope. Modern dogfights almost exclusively take place at high subsonic/low supersonic speeds, and flying slow only makes you incredibly vulnerable. The kind of turning fight you're thinking of was a thing of the past even by mid-WW2.

>>32413755
i would have thought with off-boresight aim-9xs that having a smaller turn radius would be best

>>32413778
Nope. Supermaneuverable short-ranged AAMs like AIM-9X have effectively made maneuverability like that irrelevant - no matter how hard you turn, the missile can always turn harder.

For evasive maneuvering, what you actually want to do is retain as much energy as possible while putting distance between yourself and the missile and forcing it to make corrective maneuvers to burn delta-V. Generally that means running away as fast as you can in a direction that will force the missile to make as many maneuvers as possible. Hard turns (especially those flashy post-stall maneuvers that the Flankers can do) just bleed your airspeed and make it easier for the missile to catch you.

>>32413778
Modern dogfights are so vicious that the only thing most pilots would ever see are dots in the sky and blips on the radar.

Both are trying to find the other while ensuring that their own emissions are kept low. Worst thing a pilot can do nowadays is get into a turning fight while often biologically taxes the pilot more than the plane itself. Both would be at the point trying to make the other overshoot and waste energy while getting into an advantageous position to shoot.

Dot wars. First one to launch a missile often has the upper hand.

>>32413814
So slow speed is actually irrelevant against modern missiles? if they get UFO-tier tech to instantly stop an aircraft and then immediately speed up to mach 1 and so on would that not be useful?

>>32413837
Not slow speed, low energy.

Using gravity, using minimal amount of turns to keep speed at a high constant. High energy fighters like the F-16 and the MIG21 are nimble fucks who can literally dart around heavier fighters.

>>32413852
wasnt there a test that proved that helicopters with AAMs beat out fighter jets?

thats what i was thinking of when I made the thread, like if you could get the ability to turn on a dime mixed with the normal abilities of a supersonic fighter

>>32413837
>So slow speed is actually irrelevant against modern missiles?
Yeah - low-speed maneuvering only loses you energy and makes you more vulnerable. Worse, even if you do survive the missile launch, now you're in a bad position to retaliate because you're going significantly slower than the target and you don't have as much energy to put into whatever missiles you fire.

>if they get UFO-tier tech to instantly stop an aircraft and then immediately speed up to mach 1 and so on would that not be useful?
Ironically, that might actually be useful on missiles moreso than fighters. The real problem there is that it's overdoing it - fighters max out at about 9Gs, so you only need the missile to be able to handle enough Gs to hit targets maneuvering at that. Note that those loadings are going to be far higher than 9Gs (as the missile's going to be traveling far faster than the target ideally), but even so, missile technology can comfortably outmaneuver any fighter.

>>32413882
why dont they just replace aircraft with missiles that can be piloted like a drone at subsonic speeds and then go full speed when they lock on

>>32413902
Whole bunch of reasons actually -

>Reusability
missiles are expensive as hell, but aircraft are more expensive. Throwing away an aircraft (or realistically, multiple aircraft given hit rates for missiles) at every target isn't feasible. Fighters can kind of be looked at as two-stage rockets, with the first stage being the aircraft itself and the second stage being the multiple missiles it will carry. Your proposal is not only reducing the overall payload, but throwing away the most expensive part of the system with every use.

>Range
Missiles are always a tradeoff of size, performance, and range. Better maneuverability means a stronger (and thus heavier) airframe, requiring more fuel to push a greater weight. The same comes with speed - the faster something goes, the more drag it's going to encounter, and thus the more fuel you need. However, you also have to make sure the missile can fit on the aircraft, and, most importantly, carry the appropriate guidance systems and warhead. The system you describe is going to be incredibly heavy, as it's going to have all that fuel to carry for the subsonic cruise portion, meaning it's going to be far larger than a conventional missile, sacrificing maneuverability and performance.

That's not to say that very large missiles don't exist - there's plenty of long-range SAMs, including some multi-stage ones. But those are different from what you've described.

>>32413778
off-boresight aim-9xs have made turning unnecessary because you could literally lock onto someone behind yourself and the missile will just turn around after being fired and hit them. that will actually be the SOP for F-35s after they've merged with enemy a/c rather than dogfighting. having better sensors and stealth so you can see the enemy and shoot at him first is more effective than being able to turn well.

>>32413965
If an AIM-54 can go 100 nautical miles at mach 5, doesnt that mean it could go 1000 nautical miles at mach 0.5? Couldn't you just go 200 miles to a target area, 200 miles back if no target presents itself and retrieve and refuel it? Maybe this is totally wrong because that range relies on an unpowered glide or someting

>>32414018
also couldn't you just use one of those over the horizon balloon radars to guide the missile so you're not throwing away money after each use

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>>32413700
>a ducted fan driven by a small turboshaft would work.

>>32413598
The biggest obstacle is the plan is retarded and has no actual benifit whatsoever.

Those planes had tighter turning radii because they were slower. Turn radius is a function of velocity and bank angle which can be computed with this simple equation

V^2/(11.26*tangent of the bank angle)

V is knots and Output is radius in feet

Source: I'm a professional pilot and professor of aeronautics.

>>32414018
No. There's this factor called specific range for aircraft analysis - effectively, how far you go per unit fuel weight. Specific range varies with fuel, and usually it peaks at whatever the design condition is. For rockets and ramjets - the propulsion systems used on missiles - the specific range is highest around their top speed. They burn fuel too fast to be useful at slow speeds.

>>32414045
The advantage of fighters is that you can maintain patrols closer to the target area than a traditional air defense network can. An aircraft orbiting 50nmi away from the target is going to be able to respond faster and more flexibly than a missile 250nmi away.

>>32413548
>WW1/2 planes turn tighter than modern fighters don't they?
G-force is a thing. Modern fighters can make sharp turns, but the pilot will grey out

>>32413635
That's ridiculously complicated

>>32413875
That had nothing to do with turn radius.

The helos "won" because they were camping out at NOE, and the fighters had a hard time detecting them against the terrain, whereas the helos could easily detect and target the higher-flying jets.

In a sense, the helos were "stealthy"--they blended in with the terrain. Imagine a helo hovering around a forest, and you are in a jet at several hundred (or thousand) feet, trying to acquire it visually.

Of course, improved radars have swung the pendulum back somewhat, and DAS should swing it heavily. And, helos don't always fly NOE, especially when on something like an air assault mission.

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>>32413548
>hybrid jet/propeller fighter jets

You mean a turbo prop?

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>>32413548
but that doesn't make any sense, disregarding the fact that it aerodynamically impossible to anywhere beyond mach 1 with a propeller due to the drag produced
The engine doesn't dictate the turning capability, the wings do.
That's why slow planes are designed with huge wings and fast ones get little stubby wings. If you have big wings and you're going really fast, they will shear off and you die. If you have little stubby wings and you're going slow you stall and die too. It's all about lift.
It sounds like what you're asking for is a plane that can fly at breakneck
speeds yet can still has good maneuvering capabilities. It sounds like you're asking more about Oblique wings, which fold into the fuselage as the aircraft goes faster, reducing the chance of the wings breaking apart. The wings extend as the plane slows, in theory retaining the same amout of turning capabilites.
https://en.wikipedia.org/wiki/Oblique_wing

As a side note the Soviets did experiment with a propjet configuration, the I-250, but was later scrapped.

>>32413548
Physics don't work that way, thats why

>>32413837
Slow speed is relevant to fast aiming of your missiles for attack.

>>32413548
>Why don't they...

When will you finally fuck off?

>>32413548
Was that the tu-95? Or am i mistaken?

>>32413548

Because the F-35 was made and for all the shit it gets it's able to do everything a prop can do without needless complexity; it can slow down to a near hover and turn on a dime compared to conventional jets.

Why don't they just weaponize hot air balloons

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>>32419149
The Republic XF-84H "Thunderscreech" or "Mighty Ear Banger". Powered by a turbine engine that was mated to a supersonic propeller

Apparently the loudest aircraft ever build. On the ground the prototypes could be heard 25 miles away. Also had the habit of inducing severe nausea and headaches among ground crews and a seizure.

A squadron flying over would have been an life changing experience I think.