http://m.nzherald.co.nz/nz/news/arti...ectid=11828807
Printable View
Having quite a few hours in both R22 and 44 I reckon they should put a wind strength restriction on them that differs from the manual.
They can be pretty scary in anything over 25knts in mountainous areas.
But if you strictly follow procedures in those conditions they will get you home.
Sent from my SM-G935F using Tapatalk
Just to get this in my dumb engineer type brain.
For you clever pilot type fellas. Mast bump would come about from a negative g situation yes? like turbulence or up/down drafts caused by mountainous terrain?
Sorry if my terminology is off .
Yes turbulence, but also the main cause with the robby is large or abrupt control adjustment at high speed and light weight creating zero g on the mast.
Treated right as Dave said they are good.
https://uploads.tapatalk-cdn.com/201...1647db4540.jpg
Sent from my SM-G930F using Tapatalk
could it be that we do things here with them they were never really designed for??
I was under the impression that they were originally designed as a "commuter helicopter"
The aircraft affect from neg G is a right roll. well more like a really fast snap roll to the right.
The natural reaction is left cyclic. But that lead's to catastrophic events. The real recovery is aft cyclic. As R93 said....unnatural to what the pilot is seeing.
It isn't just confined to Robinsons. Any two bladed helicopter can be effected.
However.....Robinson has had many many blade failures. Both departing in flight, to cracking. There was a series of blades coming off in flight in the 90s.
For me, thats unreliable.
I will never fly one again.
Robbie lovers will give me shit. But tons crash, mostly unexplained.
Robinson will never make composite blades, or make it a 3 bladed system which mast bumping doesn't occur in as it admits to design flaw. Robbies rotor design is completely different to any other 2 bladed heli.
Happy to go into more Principles of flight to explain MB more.
This is not meant to be in any way an analysis of any of the accidents mentioned in the above posts, but will hopefully help explain what they're referring to as mast bumping.
Mast bumping is generally accepted as being caused by incorrect lateral cyclic inputs when the aircraft is in a 'negative g' situation.
'Negative g' can be caused by either turbulence, or induced by the pilot by 'bunting' the helicopter over as brads correctly explained.
If the 'negative g' unloading is sufficient enough, the thrust vector from the tail rotor can cause the fuselage to roll while the disk is in an unladen state.
The correct action is to first gently apply aft cyclic to regain the disk loading (to make the fuselages weight hang from the blades again) before any lateral (sideways) input can safely be made.
However, if lateral cyclic is used first to counteract this apparent uncommanded roll, the blades can flap excessively and possibly contact the mast with the inner head assembly at the blade root end.
Two bladed teetering systems are particularly susceptible to this phenomenon and pilots are trained to understand, identify and correct this phenomenon associated with 'negative g' situations.
I have been trained in low G recovery as much as anyone but I have no idea if I would react in a real event accordingly.
Low G according to the report took my best mate. He was a 10000 hour pilot with above average skill. He has averted several emergency situations including failed tail rotor at AUW.
Total engine failure during a climb and in a turn at 200 AGL. Yet a bit of wind got him in a R22.
I am with WW. I doubt I will ever steer one again. I have flown in winds that caused my ass cheeks to rip a bit of the seat off😆
I was flying around in an area about an hour before 2 men lost their lives in an R22 due to suspected turbulence. It wasn't pleasant.
Sent from my SM-G935F using Tapatalk
There are several factors that can contribute/cause mast bumping, negative g loading, low rotor rpm, turbulence, light weight & high speed & incorrect pilot inputs.
Even the most experienced pilot can't predict when turbulence might occur all the time, the problem in the Robbies is if you make the wrong input it's all over, there's no second chance. Give me a H500 any day
The two blade teetering head design is not peculiar to Robinsons.
Among those heads I've maintained and overhauled are the Bell 206, and Hiller UH12-E and Soloy conversions.
Others are any of the Bells, from the Bell 47 (Souix in the RNZAF), UH1-D ( Iroquois) and civil derivatives up to the 212/214, and the AH-1 Cobra......
Mast bump is a possibility with that head design, but none of those machines mentioned fall out of the sky with the regularity of the Robinson.
Pretty easy for Robinson to point the finger at the pilot, when for the majority of the time the poor bugger isn't around to defend himself.
Myself and another member here had first hand experience of these POS's, we were interviewed by NZCAA as the last people to ride in a well known operator's R-66 prior to its fatal crash while returning to base after dropping us into our block. The thinking was he encountered turbulence/burble going through a high pass and the disc became unloaded, the mast bump scenario. RIP Mark.
"Death on a budget" is how I've heard a high hours fling winger refer to them.
I save my hard earned and pay for the 500...
B. ( Fixer of flying objects since Feb 7, 1977 )
Most if not all operators in the Queenstown arena longer operate them. The risk to their business is too hight to have a fatal in a R44 when they have so much bad press.
Any helicopter can have a accident. And everyday when I fly i remind myself of that.
I consider myself a safe, cautious pilot and have flown all over the place. NZ, Canada, Papua New Guinea, Australia.
But i consider the risk to myself goes up vastly when flying the robby. I have a lot of time in Bell helicopters also and I certainly do not have the same risk assessment compared to the Crapinson Heli.
On a side note, if I'm Not the pilot and getting flown into the bush. h500, AS350 and thats it.
A while back I made a decision to not be a passenger in a robbi, after reading all this I glad I made that decision.
The difference between the bell heli's etc & the Robbies is they have high inertia blades whereas the Robbies have low inertia blades which don't help. A mate used to have a Jet ranger years ago & said there was enough inertia left in the blades after doing an auto rotation to lift it up again.
When Over the Tops one went in, the weather was apparently good so a couple of these accidents have a ? Over them
Also the fact Robinson does and still have blade issues.
The modification for the dash 7 blast is fu*ked in my opinion.
Tin snips!!
https://www.youtube.com/watch?v=c2aPqgFq3A4
I was shocked when I saw this. This is after multiple cracks worldwide. A full recall would have been better. But nah, get the tin snips out!
Dash 7 blade I meant.
Some of the results of the mod look bloody ugly.
Well I have flown onto and off purseiners for work quite a few times but only the once in an R22 and that was enough.
500's and Jet Rangers feel positively safe compared to a robbie
Unfortunately most of the vessels bar one have gone to robbies due to maintenance cost and the remaining one was sold last week so I hear
Living in the salt ontop of a boat does not in my opinion make a great living place for a helicopter full stop
Fortunately with my change of employer I may never have too set foot on another seiner again
Haven't flown in a Robbie for years, when I was at school I had a holiday job with the pest board and we baited all the little islands in the waitaki river ( how/why there are actually possums living on them is still beyond me) and we did heaps of flying in a 22, he would drop us off, we would run a bait line and then radio him to take us to the next island, I thought it was great fun, and I got paid for it, couldn't believe my luck!
Now I'm a little older and questionably slightly wiser, you would have to pay me a shit tonne of money to fly in a Robbie
Had a close call in one coming into land at 1600m once, the pilot just yelled "hold on" as we hit the ground hard then she was back up and then down just before a major drop off - I told him it was my first time in a 22, he said nearly your last ......
Flew in one last week, just so cheap, $300 one way flight to the tops is so affordable, where if it was a 500 I suspect it would be around $600
Sent from my iPhone using Tapatalk
Flew in one last week, just so cheap, $300 one way flight to the tops is so affordable . Unfortunately they are know for the "one Way flights "
No offence mate but unless you have a midget pilot that weighs 40kgs and running only 20mins fuel an R22 is over weight with a fella as big as you in it, at sea level.
No way would I have ever flown you with a pack and rifle up too the tussock in 1 load unless the wind was favorable.
Sent from my SM-G935F using Tapatalk
Wayne Pratt of Karamea caught/killed over 7000 deer in the early model Robbie and uses the R44. He is not dead. Phil Janssen was full time on venison recovery in an R22 for many years and is still alive.Rule of thumb is over 20knots in the R22 and you are in danger country. In the hands of a skilled pilot there is nothing wrong with the R22 including heli hunting. Just pick your pilot.
Yeah, shouldn't even be doing that but everyone does.
How many times can ya stretch a rubber band before it breaks?
Their blades are crap imo and every heavy load adds a little more stress to them and the drive train as they struggle in their plane of rotation.
Saying someone has survived because of their skill until now, is neither here nor there and basically an insult to the pilots that have lost their lives in them. (Even tho I am sure that's not your intention.)
Where does 20knts fit in?
7000 deer is only a couple seasons on venison. I know Wayne has done a few more than that. Hope he has many more. But I am sure he would be the first to admit that the R22 doesn't leave much to chance.
Sent from my SM-G935F using Tapatalk
VC: I think he was talking wind speed..
What I was going for is 20knt "measured" at presumably the local airport could mean back eddy's, up and down drafts and funnels that turn 20knt into 40-60knt in places.
presumably 20knt would be no problem at all over the likes of the outback of Australia(dust discounted) vs the mountains of NZ ?
Yup. You're onto it.
If the machine weather cocks when in balance, it is too windy to be in the mountains imo.
A 20+ knt S easterly or Northerly was unpleasant to fly in when up some major South Westland valleys in a 22 or 44.
We never hunted in anything like that as the animals were not about either.
Sent from my SM-G935F using Tapatalk
Mast Bumping: Has New Zealand Pilot Culture Cost Lives? - Heliweb Magazine Some might find it interesting.
I've got/had a pretty awesome photo of Wayne using his Robbi to herd a big red stag towards my brother on the ground in Argentina.
Tell me you guys who travel the world flying helicopters, is there a problem with "mast bumping" with 22 and 44 Robbies elsewhere.
If you read the article posted above by Snowgrass it seems NZ has a very high rate compared to US.