Blackhawk
Well-Known Member
Not really. Most of the time part of the retreating blade is operating in the stalled region in forward flight. I taught combat maneuvers in the Blackhawk and it was very maneuverable.
3 things about helicopters...
- Thread starter PGT
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Not really. Most of the time part of the retreating blade is operating in the stalled region in forward flight. I taught combat maneuvers in the Blackhawk and it was very maneuverable.
juan valdez
Well-Known Member
Osprey has them. I thought all helo's did?
Technical name was mast nut.
USMC pilots just do a quick walk around. Takes less than 2 minutes. But the enlisted crew has already done everything else and has bird to engine start when the pilot comes out.
From what I understand of AF things are way different. Like the crew chiefs are a different job than they are in Marines, I think AF calls them flight engineers. And I guess FE's don't do any mainteance from what I've been told.
We once found a watch in the driveshaft section on an acceptance inspection of a new aircraft from factory.
Sol Rosenburg
Well-Known Member
I knew a guy that had a mechanic leave a crescent wrench on top of the engine wedged under the fuel rails. It easily rode 15 some hours in there and luckily didn't stop any spinny things from spinning freely.
juan valdez
Well-Known Member
Crazy!
Someone once left a vacuum attachment in the engine compartment, about a 2 ft long piece. The CC was a crusty old Gunny who found it. Needless to say we, because no one came forward, got a pretty good ass chewing over it, even though it was only plastic and nothing for it to really damage, the fact taht someone over looked a piece so big was unbelievable.
Someone once left a vacuum attachment in the engine compartment, about a 2 ft long piece. The CC was a crusty old Gunny who found it. Needless to say we, because no one came forward, got a pretty good ass chewing over it, even though it was only plastic and nothing for it to really damage, the fact taht someone over looked a piece so big was unbelievable.
Blackhawk
Well-Known Member
We had a good postflight inspection by one pilot. For some reason he decided to pop open the engine cowling... and noticed before he opened it that there was an unusually large amount of heat coming off of it. After letting it cool off it was popped open and it was found that two sections of the engine had come loose. Hot exhaust gas was being vented into the engine compartment. Parts of the aircraft frame and beams were warped by the heat- not something you normally find on a parts shelf. The Army had to wait for a break in the production line at Sikorsky to have them make new ones. When we left theater 9 months later the aircraft was still sitting in the depot down in Arifjan.
Blackhawk
Well-Known Member
Osprey has them. I thought all helo's did?
Technical name was mast nut.
Not if you have a fully articulated rotor system. The rotor hub in the Blackhawk is a single piece of titanium. If I remember correctly the blades are held in place by elastomeric bearings and a backup retention bolt. Never heard of a blade coming off.
PGT
Well-Known Member
How often have you seen the cyclic runaway that requires 130lbs to keep it down and the AFCS (I think), the unit that keeps you stabilized go out?
In the Chinook I've never heard of anyone having a cyclic runaway (or thrust or pedals either since they are all connected), but the AFCS goes out all the time - most of the time intentionally for training. The first time flying with the AFCS off is like trying to stay on a bucking bull while covered in KY, but you get used to it.
Teller1900
Well-Known Member
"C'mon, think positive."
The Unit. Too easy. That was Dirt Diver that said that, though. Bob was the pilot.
PGT
Well-Known Member
Flying with it off wasn't too bad, I can't imagine hovering though.
Mike H
Well-Known Member
^^^ Stole my nutrients
juan valdez
Well-Known Member
the j nut doesn't hold the blades on, it holds the hub on. Whether or not the hub is a single piece has nothing to do with the j nut.
On the V22 it has 3 blades each one held to the hub with a giant 'bolt' which isn't really a bolt at all just a giant tube which functions as a bolt. Well I guess that is a bolt but not in the general sense. Each blade has elastomeric bearings that allow the blade to flex IIRC, in other words absorb the vibes and the feathering that takes place. These were attched to the grip. Then each of those three are attached to the yoke. Then the j nut holds it all down to the proprotor mast.
Blackhawk
Well-Known Member
If I remember correctly from the UH-1H (it's been over 15 years since I was last in a unit that had them), the J nut actually kept the blades on the hub since it was a teeter totter type rotor system attached to the mast. J nut comes off and the blades come off. It has been a while, however.
juan valdez
Well-Known Member
Honestly, not sure.
Only aircraft I've ever worked on was the V22. From everything I've been told from others though, the Osprey program has quite an eclectic mix, the J nut is always the nut that holds the hub to the mast.