Bell 360 Invictus readies for flight but still no engine
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Now with pop out seating for carrying external troops.
From a technical respect, the MH-60M uses the same gearbox as the UH-60M, but to be fair that is mostly the L Model Main Transmission with the Navy Tail Takeoff assembly to allow the Rotor Brake installation. The USAF HH-60G Nighthawks did something similar, and also have the rotor brake.
There is capacity to add an additional take off pinion/assembly (like the Navy did for the MH-60R's dipping sonar pump/motor) onto the Main Module, but I don't know if the MH-60M options include something like that. (This perspective is a few years old, so something new may have come up that I am not aware of).
I translated (in my head) CT7-8B5 as being the descendant of the YT-706, a 2600 hp engine of the T-700 / CT-7 family. My apologies if that's in error.
It strikes me as improving single engine performance, but I wonder at how they had to re-rig the governors / fuel control to avoid overtorque on the main transmission.
That's a substantial power available increase from the standard T-700 to the 2600 hp engine.
Adding the 901 (when it arrives) ... looks like more of the same. The suggestions above about putting a beefed-up transmission onto any Blackhawk with the new engine seems prudent. (But I wonder if that's affordable, across a fleet of over a thousand H-60M helicopters?)
Many thanks to SplineDrive for the insights on the S-92 transmisions limitations. I had always understood that the backward compatibility idea was intended to pay off downstream (and informed not using a 5 bladed main on the 92) but I guess that hasn't panned out.
Back on the Invictus topic:
As to the pop out seating mod: sure, sign me up to travel strapped-in to the outside of a helicopter doing over 100 knots.
Wait a sec, no, I'll not buy that ticket to ride.
There is capacity to add an additional take off pinion/assembly (like the Navy did for the MH-60R's dipping sonar pump/motor) onto the Main Module, but I don't know if the MH-60M options include something like that. (This perspective is a few years old, so something new may have come up that I am not aware of).
I translated (in my head) CT7-8B5 as being the descendant of the YT-706, a 2600 hp engine of the T-700 / CT-7 family. My apologies if that's in error.
Rated in the 2,600-shaft-horsepower (shp) class, the CT7-8B5 was certified by the U.S. Federal Aviation Administration (FAA) in 2004. The CT7-8B5 features an advanced, higher-flow compressor designed with new three-dimensional aerodynamic (3D Aero) technology, a modern full authority digital electronic control (FADEC) system, plus hot-section and turbine components proven in millions of flight-hours on GE's family of commercial engines.
That's a substantial power available increase from the standard T-700 to the 2600 hp engine.
Adding the 901 (when it arrives) ... looks like more of the same. The suggestions above about putting a beefed-up transmission onto any Blackhawk with the new engine seems prudent. (But I wonder if that's affordable, across a fleet of over a thousand H-60M helicopters?)
Many thanks to SplineDrive for the insights on the S-92 transmisions limitations. I had always understood that the backward compatibility idea was intended to pay off downstream (and informed not using a 5 bladed main on the 92) but I guess that hasn't panned out.
Back on the Invictus topic:
As to the pop out seating mod: sure, sign me up to travel strapped-in to the outside of a helicopter doing over 100 knots.
Wait a sec, no, I'll not buy that ticket to ride.
Last edited by Lonewolf_50; 5th Oct 2023 at 12:53.
John, after a raft of S-92 gearboxes cracked at the joint to the airframe, I'm not sure they're easily retrofittable to the H-60 any more once fixes were implemented. In any case, reacting the S-92's head moment on the same bolt pattern as an H-60 hasn't been without problems. I suspect the same would be true for the TGB. Physically pinning up is just one part of compatibility with a new airframe.
As I recall the problem that caused the “cracked feet” was that the fuselage mounting points were misaligned during manufacture.
The mounting points were repaired in the field and the problem did not reoccur.
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“I wonder at how they had to re-rig the governors / fuel control to avoid overtorque on the main transmission.
That's a substantial power available increase from the standard T-700 to the 2600 hp engine.“
The UH-60M engine management has protections against over speed and over temp conditions, I haven’t heard anything about MH-60M, they may have something that limits max engine torque, I don’t know how they would ingrate that into the system though.
The current main module if I’m not mistaken can handle up 120% dual engine torque(with 701D engines). It takes off like a rocket at 120% dual engine torque, in case you are wondering. 🤣
I have to assume since I don’t have access to the MH-60M -10, with YT706 engines they would only have a placard on the instrument panel similar to what the UH-60A+ had, which used the “old” Main Module, not the “Improved Durability” (aka UH-60L Main Module), with 701C/D engines that showed max dual engine torque the transmission could handle under certain conditions.
Excess power is therefore always available for conditions where the 701D would TGT or NG limit(therefore causing NR droop) before reaching the transmission torque limit, but it has to be managed to not get in trouble.
Also consider certain MH-60M components that are common to the standard UH-60M such as drivetrain or structural components also have different retirement lives, which could also suggest that the MH-60M has significant operational limitations differences, and transmission torque may be one of them.
FltMech
That's a substantial power available increase from the standard T-700 to the 2600 hp engine.“
The UH-60M engine management has protections against over speed and over temp conditions, I haven’t heard anything about MH-60M, they may have something that limits max engine torque, I don’t know how they would ingrate that into the system though.
The current main module if I’m not mistaken can handle up 120% dual engine torque(with 701D engines). It takes off like a rocket at 120% dual engine torque, in case you are wondering. 🤣
I have to assume since I don’t have access to the MH-60M -10, with YT706 engines they would only have a placard on the instrument panel similar to what the UH-60A+ had, which used the “old” Main Module, not the “Improved Durability” (aka UH-60L Main Module), with 701C/D engines that showed max dual engine torque the transmission could handle under certain conditions.
Excess power is therefore always available for conditions where the 701D would TGT or NG limit(therefore causing NR droop) before reaching the transmission torque limit, but it has to be managed to not get in trouble.
Also consider certain MH-60M components that are common to the standard UH-60M such as drivetrain or structural components also have different retirement lives, which could also suggest that the MH-60M has significant operational limitations differences, and transmission torque may be one of them.
FltMech
For Robbo Jock:
Just sit 'em on the wings, save all that expensive pop-out seating rubbish.
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Question is, will they come with pop out, pop out cupholders?
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Spline Drive and Albatross: Good and very relevant comments. You can imagine that mounting a main box with not only higher head moment capability, but also a 5 degree forward main shaft tilt as opposed to the Hawks 3 degrees, generated some serious redesign effort. I do not recall the specifics of their solutions, but your comments hit the high points. Added to those considerations, don’t forget that the solutions had to meet all of the Army’s now standard crashworthy and ballistic survivability design requirements.
