US Armed Forces cannot resume flights of part of the V-22 Osprey convertiplanes due to technical problems

Technical problems with the engines caused the US military to suspend the use of the V-22 Osprey tiltrotor aircraft for an indefinite period. On Saturday, a US Department of Defense spokesman again noted that the search for a solution to the technical problem continues.

According to the American media, the problem is rooted in poor assembly of parts connecting the Osprey engine to the propeller (technical problems with the transmission). The US Department of Defense, on condition of anonymity, told the press that the command of special operations of the Marine Corps, Navy and Air Force continue training and operations with convertiplanes, since the use of not all devices has been suspended.

There are no further operational restrictions, according to Defense News, citing a Pentagon spokesman. Tiltrotoros, in which everything is in order, are ready for departures and training. The publication emphasizes that as of the spring of 2022, the US Marine Corps had 296 tiltrotor aircraft, the Air Force Special Operations Command had 52 tiltrotor aircraft, and the Navy is in the process of receiving 44 CMV-22 aircraft purchased to support aircraft carrier strike groups.

As for technical problems, experts note an increase in cases of hard clutch engagement. Osprey crews are required to land immediately after hard clutch engagement to avoid tiltrotor crash. Previously, there were two accidents with tiltrotor MV-22B Osprey.

One tiltrotor crashed in March 2022 in Norway during a military exercise, killing four USMC Marines. The second tiltrotor crashed in California in June 2022, with five military personnel on board, all of whom died.

Such incidents seriously alarmed the military command and forced him to pay increased attention to the technical condition of tiltrotor aircraft, including problems with the transmission.

Comments

[Mavrikiy]

Technical problems with the engines led to the suspension of the use of tiltrotor V-22 Osprey US armed forces indefinitely.

And why the APU, you can fly there, even on a mortar.

[ivan1979nkl]

there you can fly, even on a mortar

Ukrainians will definitely ask for Osprey, but only after the planes

[venaya]

From the very beginning of operation, this particular tiltrotor model had all sorts of technical problems, an extremely crude design. Although I personally am a big supporter of such technical innovations, it is simply necessary to finalize the design and even the tiltrotor schemes can be better modified for increased flight reliability, especially in takeoff and landing modes.

[Azim77]

Probably in the future a hybrid scheme will appear, when the propellers are turned by an electric motor, and electricity is generated by one gas turbine. It is easier to control 2 propellers, better synchronization, electric motors change speed faster, fewer transmission units. Also, electric motors are lighter, which will reduce the load on the pylons.

[venaya]

Quote: Azim77

Probably in the future a hybrid scheme will appear, when the propellers are turned by an electric motor, and electricity is generated by one gas turbine. It is easier to control 2 propellers, better synchronization, electric motors change speed faster, fewer transmission units. Also, electric motors are lighter, which will reduce the load on the pylons.

I don’t think that this is a good idea for you, the fact is that both an electric generator and electric motors have a very low power-to-weight ratio per unit weight, that is, the weight of such a design will be exorbitant. At present, there is no longer a special need to convert its energy into an electrical equivalent to control the engine thrust, it is quite acceptable to directly control the engine thrust or, more precisely, engines, since it turns out to be more profitable in terms of weight to have an individual engine for each main rotor, but for takeoff and landing it is desirable to have auxiliary screws for two screws will hold a tiltrotor even on the deck of a large aircraft carrier, as far as I have seen, it is not always possible, not to mention smaller ships. After all, what is the situation there: around with any wind, rather large waves arise and they form endless air turbulences near the surface, that is, rotors, and taking off and landing in such conditions at low approach speeds is extremely difficult and dangerous. So the tiltrotor scheme is forced to be slightly complicated, which is not very difficult at the present time, too much time has passed, much has become clear and understandable, the question is simply in the interest of the interested parties. In my opinion it is...

[Fizik13]

Quote: venaya

... At present, there is no longer a special need to control the thrust of the engine to convert its energy into an electrical equivalent, ..

But what about the turboshaft engine and generator shown at MAKS-2021, and the Yak-40LL, though a demonstrator, but this is just the beginning

[venaya]

Quote from Fizik13

... But what about the turboshaft engine and generator shown at MAKS-2021, and the Yak-40LL, though a demonstrator, but this is just the beginning

I myself am an ardent supporter of the use of any electrics, including in areas of high power, but try to provide both economic feasibility and specific benefit in power per unit weight in double conversion of energy. In almost all cases, an increase in weight per unit of power is obtained. Try to check that position yourself, another thing is that sometimes you can still catch some benefit, but in aviation it is still too difficult to do so.

[vovochkarzhevsky]

And with such a decision, drop below the plinth? And how will replacing the transmission with personal electric motors make propeller control easier? At the same time, tell us how much weight your electric motors will have to provide the required torque without gearboxes?

[Azim77]

Quote: vovochkarzhevsky

At the same time, tell us how much weight your electric motors will have to provide the required torque without gearboxes?

So that's why I wrote that in the future. Now the weight-to-power ratio is still high for that. But progress is not worth it, compare how big and heavy electric motors were in the past.

Here is an example of one of the developments:

The founders of the Belgian startup Magnax announced the start of testing of their revolutionary electric motor by one of the European automakers. They previously stated that in a compact version for a motorcycle, such an engine would develop an output of about 1200 hp. With. And now, in a publication for IEEE Spectrum, they explained in detail how it works.

In a traditional electric motor circuit, the rotor is placed inside the stator. As the names imply, the stator is static, and the rotor inside it rotates due to the interaction of magnets that repel and attract each other when a magnetic field is generated. If such an engine is rotated without power supply, then it will begin to generate electricity itself - this is how generators work, as well as the regenerative braking system on cars that recharges the batteries.

Magnax literally turned the electric motor inside out, placing the stator in a gasket between the two rotors and calling their creation an "armorless axial flow electric motor."

The advantages of such a scheme are enormous, the creators say. The main thing is that the stator does not need to be mounted on an external frame, so the engine is compact and light. For comparison: the specific power of the Magnax prototype is 15 kW per kilogram of weight, while the BMW i3 electric motor has only 3 kW per kilogram.

Compactness saves on materials: you need 40% less copper and 20% less magnets. And the rectilinear direction of the magnetic field - from one rotor through the stator to another - makes the motor very efficient.

[vovochkarzhevsky]

So that's why I wrote that in the future. Now the weight-to-power ratio is still high for that. But progress is not worth it, compare how big and heavy electric motors were in the past.

Now the system, if simplified: two engines, two gearboxes plus a power transmission shaft (for safety).
In the proposed scheme, none of the above is removed, but two electric motors and two generators are added. The mass grows, the design becomes more complicated.
So the transition to electric motors is possible only after the creation of batteries comparable in energy intensity, weight and volume to fuel tanks.

[ProkletyiPirat]

Quote: vovochkarzhevsky

And with such a decision, drop the safety below the plinth?

1) a hybrid can weigh both more and less, because firstly, the main mass is a gearbox, and secondly, electric aircraft engines have an excellent structure with less weight
2) the problem of the tiltrotor osprey is not at all in the engines themselves, but in their location, air filtration and air flow stabilization
3) the main problem of convertiplanes based on a main rotor is completely different, there is a hemorrhagic difficult-to-track dependence on the mass of the transported cargo and its influence when switching between flight modes, the problem is solved quite simply, but I won’t write about it, let the United States spend more money

[vovochkarzhevsky]

1) a hybrid can weigh both more and less, because firstly, the main mass is a gearbox, and secondly, electric aircraft engines have an excellent structure with less weight

And you can't refuse gearboxes.

2) the problem of the tiltrotor osprey is not at all in the engines themselves, but in their location, air filtration and air flow stabilization

There are no such problems.

3) the main problem of convertiplanes based on a main rotor is completely different, there is a hemorrhagic difficult-to-track dependence on the mass of the transported cargo and its influence when switching between flight modes, the problem is solved quite simply, but I won’t write about it, let the United States spend more money

Have you heard about such a science as helicopter aerodynamics? Looks like no.
The main problem of the tiltrotor is that it is impossible to create a propeller that can simultaneously be effective both in the carrier and propeller modes. Too contradictory requirements, primarily to geometry.
Perhaps in the future, humanity will invent a way to lengthen / shorten the blades in flight, change the twist, and at the same time reliable variators, but so far, alas.

[digger]

Just like the destroyer zamvolt is an expensive project .. and zero efficiency ... so is this bogey - expensive .. complicated. and zero efficiency. Capricious .. more on repairs than in flights.

[Alex_Bora]

Quote: Azim77

Probably in the future a hybrid scheme will appear, when the propellers are turned by an electric motor, and electricity is generated by one gas turbine. It is easier to control 2 propellers, better synchronization, electric motors change speed faster, fewer transmission units. Also, electric motors are lighter, which will reduce the load on the pylons.

The developers of the unmanned tiltrotor have taken this path. Very effective control is obtained, up to landing on a KAMAZ moving along the urban cycle. I saw this video from them. But, alas, so far only development on an initiative basis.

[venaya]

The developers of the unmanned tiltrotor have taken this path. Very effective control is obtained, up to landing on a KAMAZ moving along the urban cycle. I saw this video from them. But, alas, so far only development on an initiative basis

So these are completely different weight and size characteristics of the device, with a low weight it is already possible to use electric motors there ... The fact is that with an increase in the size of the aircraft, its area is magnified in a quadratic function and the weight in a cubic one is therefore always more profitable to have a small size an aircraft, it requires for itself a lower power-to-weight ratio than full-size aircraft, especially with increased weight loads. So it’s better to play small drones with electrics there, then everything is not so critical.

[tralflot1832]

Osprey is an excellent, revolutionary machine. The first demonstration flight on the ground - 2 wounded. The first demonstration flight in front of congressmen on the Potomac River - 7 corpses. Air defense. The destroyer of dangerous witnesses, with the help of a bzdyn on the ground or water. In the latter case, there is a special cynicism - so you know how to fly, but how to swim? Cool, excellent, unparalleled machine in the world.

[venaya]

What can you do: the road of a person to the air environment is all covered in blood, the first who flew with artificial wings is prof. Lilienthal, so he also crashed to his death, although before that he had made many successful flights and really opened the way to heaven for mankind. Unfortunately, nothing goes without sacrifice in such new and revolutionary devices, and humanity is still learning from its mistakes.