For my Rotorheads- What happened here?

Velocity173 said:
I don’t mind breaking both up but standardizing it across the board would be nice. The Army doesn’t even give it a name. Just a one liner:

In some helicopters during high altitude operations, the maximum antitorque produced by the tail during a hover may not be sufficient to overcome torque even if gross weight is within limits.

LTA or LTE, as long as pilots realize the above statement can happen, that’s all that really matters.
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Speaking of max performance heli ops, do you know much about reducing tail rotor load completely so that the heli spins, yielding more straight up lifting power for confined, max gross or high DA take off ops? We've been experimenting with it in 300s but don't seem to get any noticeable improvement in spite of a high spin rate.
 
Dave Krall CFII said:
Speaking of max performance heli ops, do you know much about reducing tail rotor load completely so that the heli spins, yielding more straight up lifting power for confined, max gross or high DA take off ops? We've been experimenting with it in 300s but don't seem to get any noticeable improvement in spite of a high spin rate.
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Nope, never experimented with that. The aircraft that I’ve flown (minus OH-58) have plenty of power to get in and out of confined areas so it’s really not necessary. I make sure I’ve got HOGE power before doing a confined area as well.

I’ve observed a few percent trq decrease doing a right pedal turn coming out of a confined area but that’s about it. I would think that you’d save maybe 10 % in trq if you spin it aggressively but you’re gonna have to stop the rotation eventually. That is unless you go from spinning, get lateral speed and go through ETL. If you’re truly that heavy / high DA and you let that spin develop, I think you might also run the risk of not being able to stop the rotation as well.
 
I've definitely done takeoffs where I sure as heck didn't add any left pedal though I've never intentionally pushed right pedal to add power, that's an old logger trick and some old 'Nam pilots used it to get an extra body out of the jungle but not something to purposely do to try and increase high DA performance that's just asking for trouble.

The only person I know that did that kind of thing on purpose was my instructor. Around 2:38 in his pyro act he pulls power and doesn't add pedal

 
Velocity173 said:
Nope, never experimented with that. The aircraft that I’ve flown (minus OH-58) have plenty of power to get in and out of confined areas so it’s really not necessary. I make sure I’ve got HOGE power before doing a confined area as well.

I’ve observed a few percent trq decrease doing a right pedal turn coming out of a confined area but that’s about it. I would think that you’d save maybe 10 % in trq if you spin it aggressively but you’re gonna have to stop the rotation eventually. That is unless you go from spinning, get lateral speed and go through ETL. If you’re truly that heavy / high DA and you let that spin develop, I think you might also run the risk of not being able to stop the rotation as well.
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Yeah it is a damned hairy maneuver for actual confined spaces, we practice it in an open field. First ran across it in Vietnam Nam accounts of high GW, hot DA, confined escapes under already deadly conditions. As we get some altitude in the spin, a key is to transition into ETL as soon as possible.
 
Also, in an actual confined space, the surrounding obstacles will confine downwash momentarily, making the maneuver more productive in the quick altitude department.
 
Dave Krall CFII said:
Speaking of max performance heli ops, .
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Seen a couple Lama pilots use the spin technique moving heavy seismic drills in the jungles of SA. They would comment off-loading the T/R would add 20-30% TQ at the M/R. It wasn't something everyone did but those who mastered it was a sight to see.
 
Bell206 said:
Seen a couple Lama pilots use the spin technique moving heavy seismic drills in the jungles of SA. They would comment off-loading the T/R would add 20-30% TQ at the M/R. It wasn't something everyone did but those who mastered it was a sight to see.
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It's that 20-30% figure I've heard too, which is enticing. We'll also do a "300 Hop" take off but again, not sure of any provable value, especially with ground resonance possibilities. It's so fast though i guess there's not time for that complication.
 
Dave Krall CFII said:
We'll also do a "300 Hop" take off
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If referring to bouncing an external load on a short line to get into transitional lift then not advised. Same for using the transient TQ limits in daily ops. Both are not conducive to getting max life out of drive components.
 
Velocity173 said:
It’s amazing that no serious injuries occurred on this one.
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Too bad he didn't have a real T/R. Might had made it. Word I heard was the wind was swirling/gusting and blew the air flow off the tailboom resulting is loss of control. Add in he was at max hover alt of 11k feet so his options were slim and none once the people jumped onboard.
 
Bell206 said:
If referring to bouncing an external load on a short line to get into transitional lift then not advised. Same for using the transient TQ limits in daily ops. Both are not conducive to getting max life out of drive components.
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Interesting. No, the 300 Hop maneuver is from a low hover to a quick set down such that all the shock absorbing springs are compressed and their stored energy then quickly used in the take off.
 
Bell206 said:
Too bad he didn't have a real T/R. Might had made it. Word I heard was the wind was swirling/gusting and blew the air flow off the tailboom resulting is loss of control. Add in he was at max hover alt of 11k feet so his options were slim and none once the people jumped onboard.
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Yeah I’ve read the MD600/900 lack authority at heavy weights and altitude. Heard rumors about NOTAR lack of authority in general but not sure how much of that is fact.
 
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Dave Krall CFII said:
Interesting. No, the 300 Hop maneuver is from a low hover to a quick set down such that all the shock absorbing springs are compressed and their stored energy then quickly used in the take off.
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No wonder i was always bleeding the gear dampers back in my limited 269 days.......
 
Velocity173 said:
Heard rumors about NOTAR lack of authority in general but not sure how much of that is fact.
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I was around the first 900s and most pilots stated the tail authority was there. You could mash the pedal and it moved... added 40% TQ to the equation but no issues until the wind was blowing from behind or high/heavy. Since most of the anti-torque is through the fan air moving out vents over the tailboom skin any disruption by a tail wind would make for interesting hovers like our mountain guy above.
 
Dave Krall CFII said:
Ya lost me...
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The gear dampers are oleo struts. Usually the nitrogen charge would need servicing on a regular basis if the owner was hard on the gear, which was a pain too. Sometimes the damper strut seal would blow out which required disassembly, bleeding, etc. to fix. So any "extra" duty put on the gear dampers would increase our job security. Same with those hyd M/R dampers...........
 
Dang, who the heck you training with to teach you dumb stuff like bounce off the oleos. Those are there to help prevent ground resonance.
 
jaybee said:
Dang, who the heck you training with to teach you dumb stuff like bounce off the oleos. Those are there to help prevent ground resonance.
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If in the last 30 years flying I had a dollar for every time some dufus questioned negatively the validity of both standard or advanced flight maneuvers that they didn't understand, couldn't properly perform, or were afraid of, I'd have like, a whole bunch of dollars! And if it included the same from anonymous internet posters it'd be 100 times more.
 
Nice. Can't validate your position so call me a name like a child.

I only happened to learn how to fly and wrench on helicopters from a guy that has most likely forgotten more about the 300 then you'll ever know.
 
Dave Krall CFII said:
Interesting. No, the 300 Hop maneuver is from a low hover to a quick set down such that all the shock absorbing springs are compressed and their stored energy then quickly used in the take off.
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You use this bounce technique as a way of getting out of a confined area (OGE) or is it used to get through ETL?
 
This one wasn’t long ago.
 
Velocity173 said:
Maint issues. Sad. Some of the guys I work with are former 206 tour pilots. Hearing their stories, I’m glad I never had to go that route to build time.

https://app.ntsb.gov/pdfgenerator/R...tID=20160218X71040&AKey=1&RType=HTML&IType=FA
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Yeah. I’m still waiting on the final report from 16760, the 206L crash from Smoky Mountain Helicopters. I’m almost sure it was mechanical, but I dunno. I rode along on several flights with my buddy when he was flying up there in that chopper. Nice perk for friends and family actually...
 
That's the short shaft failure in Hawaii, that's a rough one to recover from.

Yea I don't think I ever heard anything about Smoky Mountain yet.

Anybody want to start a poll how long till we hear about a bunny hopping 300 accident :eek2:
 
Velocity173 said:
You use this bounce technique as a way of getting out of a confined area (OGE) or is it used to get through ETL?
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Will have more on this soon, have to contact the guy that told me about them who really actually sounded like he used them from time to time. He owned and timed out (2) 300s after Korea and may not even be around anymore.
 
Dave Krall CFII said:
Will have more on this soon, have to contact the guy that told me about them who really actually sounded like he used them from time to time. He owned and timed out (2) 300s after Korea and may not even be around anymore.
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Well it’s not entirely unheard of as far as getting through ETL. The Vietnam guys used a sliding bouncing type take off when they couldn’t hover. A rolling take off on a Black Hawk uses about 20 % less trq than hovering. I’m just curious as to how much trq could be saved in a skids helo. I’d think unless it was wet grass, the friction from the skids would make up for most of the trq gain of not hovering??? I’ve just never heard of any real world numbers on that technique.
 
Velocity173 said:
A rolling take off on a Black Hawk uses about 20 % less trq than hovering.
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Speaking of rolling take-offs... years ago in my SA days, hopped a ride on a MI-17 at a local airport to hand-carry a start/gen to a broke 206 at a jungle sismo camp. The local military was running "commercial" ops to make ends meet. Needless to say after I jumped on at the spur of the moment, I noticed the entire cabin was full of 55 gal drums of JP5. Unsecured. Seems the rivers were low and they couldn't barge the fuel to the camp. After about a 1000ft rolling take off we got airborne. Once we landed I inquired with the flight engineer--who I had been known to share a few beers with--why the long roll. I figured to keep it in the green. Nope. Needed the 1000 feet to keep it in the transition TQ limit. Got to hand it to the Russians, they make some bullet-proof aircraft..........
 
Bell206 said:
Speaking of rolling take-offs... years ago in my SA days, hopped a ride on a MI-17 at a local airport to hand-carry a start/gen to a broke 206 at a jungle sismo camp. The local military was running "commercial" ops to make ends meet. Needless to say after I jumped on at the spur of the moment, I noticed the entire cabin was full of 55 gal drums of JP5. Unsecured. Seems the rivers were low and they couldn't barge the fuel to the camp. After about a 1000ft rolling take off we got airborne. Once we landed I inquired with the flight engineer--who I had been known to share a few beers with--why the long roll. I figured to keep it in the green. Nope. Needed the 1000 feet to keep it in the transition TQ limit. Got to hand it to the Russians, they make some bullet-proof aircraft..........
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Yeah, the Hip is a solid aircraft. Doesn’t have a lot of fluff but it gets the job done. Friend flys them and can’t understand why Afghanistan is replacing them with Black Hawks.
 
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