Cairns Helicopter Crash
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Thats a new one! A farking gearbox? Never new the robbys had them! Wheres the best place to find final reports for these accidents when there actually issued?
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Wheres the best place to find final reports for these accidents when there actually issued?
It may well be a worth while comment that the TRFG has disappeared, by the look of one of the photographs. It could have been torn off when the remainder of the rear far'n end got snotted against yon tree as cann be seen by the bent metal.
This may have been very convenient as hard objects like that have been known to help cease rotation in a most uncompromising but helpful manner.
Had the FTRG departed whilst still above the flora, then almost certainly (given the Cof G displacement which would have happened as evidenced from photos of the farn heavyweight and layabout dispossesed pax) [see accompanying article] then the last thing that our illustrious pilot could have been attributed with might have been, "F' Never Seen That Before", as his soul sailed f'n skywards.
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I hear the ATSB will not be investigating
Is this because of Kevin 07's razor gang policy? surely they're not acting only on a pain killer drug induced statement from the driver.
Let's assume for a second that here may have been a malfunction to the T/R drive shaft and our intrepid driver did not get the throttle off as you're supposed to thus giving the flight path as described by the onboard witness.
had there been any weaknesses in the Drive shaft system, for whatever reason, and given the desciptions of the wind, load and mission profile, there is every chance that such a weakness could have been exploited given the excess of power and pedal that could have being used.
BTW was it charter or A/W?
to digress, for a second, i see recently where the oz media gave 'Kevin 07' a real drubbing as a dork recently. The reason was that on his recent trip to Japan he stood up in front a learned audience and told them all in Japanese, "Hi, my name is Kevin and I come from Australia".
most of us can't wait to see if he gets invited to the States to see whether he has enough of a grasp of their lingo to pull the same stunt.
but as i've said before, don't blame me, I didn't vote for the c**khead
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What is it called when your left pedal is on the bubble and you are still yawing right? with low airspeed, high gross weight and high density altitude? LTE
LTE doesn't exist. It's an ar**-covering invention. The simple correct term is loss of control by a pilot failing to recognise the warning signs.
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I admit to being one of the uneducated when it comes to these things.
I have heard of a similar incident where the pilot experienced a sudden jolt and severe shaking with both pedals going to the floor.
Does that sound like a so-called LTE event?
Just curious.
Di
I have heard of a similar incident where the pilot experienced a sudden jolt and severe shaking with both pedals going to the floor.
Does that sound like a so-called LTE event?
Just curious.
Di
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kflexer - no its not (well it is, but only by the uneducated), if you do a search you will find Nick Lappos addresses this fallacy at length. If I remember correctly it was a term invented by Bell to avoid liability in the courts when explaining why 206's were crashing. The fact is the tail rotor is just too small to do what is asked of it at times. If you read page one you would have noted that JimBall in post #18 quite correctly said
Quote:
LTE doesn't exist. It's an ar**-covering invention. The simple correct term is loss of control by a pilot failing to recognise the warning signs.
Today 10:35]
Quote:
LTE doesn't exist. It's an ar**-covering invention. The simple correct term is loss of control by a pilot failing to recognise the warning signs.
Today 10:35]
"loss of control by a pilot failing to recognise the warning signs"
Flying too slow at a high density alt. and with a high power setting in a machine that has limited T/R authority to begin with could cause "LCBPFRWS" Its just easier to call it LTE loss of tail rotor effectiveness , It is always pilot induced and is always avoidable. It is not some mysterious aerodynamic force that happens when we least expect it, it is simply what happens if we fly our machines outside their capabilities. In pretty much every country I have worked in they call it LTE. You and Nick can call it whatever you want
I have heard of a similar incident where the pilot experienced a sudden jolt and severe shaking with both pedals going to the floor.
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kflexer - The following is what Nick Lappos has to say on LTE. (Nick was test pilot for Sikorsky and did the work on the 76 - among other things).
The real skinny on LTE is simple and quite easily stated:
All rotors lose thrust when operating in disturbed air, including tail rotors, main rotors and fantails. LTE sets in when there is so little thrust margin that the loss of the maybe 5 or 10% of the thrust is enough to kill you. With a really marginal design, that slight loss of thrust unleashes the massive main rotor torque, and the aircraft bites its pilot big time. I cut my teeth on the old AH-1G snake, with its way too small tail rotor, and had at least my share of 360 turns while trying to get over someplace to cut the throttle.
LTE only affects those helicopters that have too little tail rotor thrust margin. Period. It is really not LTE it is "Not Enough Tail Rotor".
LTE happens when the tail thrust is consumed by several possible upsetting factors, and when the remaining thrust, by marginal design, is simply inadequate. Yes, inadequate. These possible tail thrust reducers are:
1) main wash into the tail rotor, as illustrated in the LTE handouts that we've all seen.
2) using somewhat too much main rotor thrust (collective pitch) at the bottom of an approach, especially in critical tail thrust conditions. I can touch the left pedal stops on any helo by simply raising the collective pitch until main torque washes out all tail margin. One inch more collective and WATCH out! You get LTE, surprise, surprise.
3) terminating an approach with a critical wind condition, where the wind is a few knots more than your helo can stand.
I did a study on "LTE" accidents to support a regulatory change meeting I was attending, and , wow, it was some surprise to find that about 95% of all LTE accidents were restricted to one brand name, and all LTE accidents were experienced by helicopters with very little cross wind capability.
The cure for LTE is quite simple - get a helicopter with a bigger tail rotor, as proven by the certified crosswind capability. Don't get in one that has an LTE history, and don't buy the bull that LTE is a pilot error problem. Don't buy into the new certification rules that allow you to operate with a helo that has no crosswind capability. If you do, get a good helmet, and a good insurance agent.
BTW, the LTE study that I did was opposed by an engineering manager from that particular manufacturer because "LTE is a pilot error problem, plain and simple" I asked how so many bad pilots were flying his helos, and expressed our luck that so few of these dumbos were flying all the other brands.
In the fantail, sometimes I can feel the main rotor wash flow into the tail, the pedal moves a few percent the noise increases, and that is that.
The big tail surfaces on the fenestrons and fantails are because the fan doesn't respond to small yaws, so the aircraft will snake a bit, unless the vertical tail is big enouigh to keep the nose ahead of the tail. On regular tail rotors, the tail rotor responds strongly to change thrust when some sideslip develops, and the yaw stability to small disturbances is strong. In fact the tail rotor area is as powerful as a vertical fin that is about 4 to 8 times bigger than the tail rotor.
This is one of the reasons why the Fantail is able to snap turn, because the fan doesn't care where the wind is from, it keeps its thrust and bending closer to normal. Under big sideslips, a tail rotor is positively screaming from the big stresses it develops. With the same maneuvers, the Fantail is calm as can be.
The real skinny on LTE is simple and quite easily stated:
All rotors lose thrust when operating in disturbed air, including tail rotors, main rotors and fantails. LTE sets in when there is so little thrust margin that the loss of the maybe 5 or 10% of the thrust is enough to kill you. With a really marginal design, that slight loss of thrust unleashes the massive main rotor torque, and the aircraft bites its pilot big time. I cut my teeth on the old AH-1G snake, with its way too small tail rotor, and had at least my share of 360 turns while trying to get over someplace to cut the throttle.
LTE only affects those helicopters that have too little tail rotor thrust margin. Period. It is really not LTE it is "Not Enough Tail Rotor".
LTE happens when the tail thrust is consumed by several possible upsetting factors, and when the remaining thrust, by marginal design, is simply inadequate. Yes, inadequate. These possible tail thrust reducers are:
1) main wash into the tail rotor, as illustrated in the LTE handouts that we've all seen.
2) using somewhat too much main rotor thrust (collective pitch) at the bottom of an approach, especially in critical tail thrust conditions. I can touch the left pedal stops on any helo by simply raising the collective pitch until main torque washes out all tail margin. One inch more collective and WATCH out! You get LTE, surprise, surprise.
3) terminating an approach with a critical wind condition, where the wind is a few knots more than your helo can stand.
I did a study on "LTE" accidents to support a regulatory change meeting I was attending, and , wow, it was some surprise to find that about 95% of all LTE accidents were restricted to one brand name, and all LTE accidents were experienced by helicopters with very little cross wind capability.
The cure for LTE is quite simple - get a helicopter with a bigger tail rotor, as proven by the certified crosswind capability. Don't get in one that has an LTE history, and don't buy the bull that LTE is a pilot error problem. Don't buy into the new certification rules that allow you to operate with a helo that has no crosswind capability. If you do, get a good helmet, and a good insurance agent.
BTW, the LTE study that I did was opposed by an engineering manager from that particular manufacturer because "LTE is a pilot error problem, plain and simple" I asked how so many bad pilots were flying his helos, and expressed our luck that so few of these dumbos were flying all the other brands.
In the fantail, sometimes I can feel the main rotor wash flow into the tail, the pedal moves a few percent the noise increases, and that is that.
The big tail surfaces on the fenestrons and fantails are because the fan doesn't respond to small yaws, so the aircraft will snake a bit, unless the vertical tail is big enouigh to keep the nose ahead of the tail. On regular tail rotors, the tail rotor responds strongly to change thrust when some sideslip develops, and the yaw stability to small disturbances is strong. In fact the tail rotor area is as powerful as a vertical fin that is about 4 to 8 times bigger than the tail rotor.
This is one of the reasons why the Fantail is able to snap turn, because the fan doesn't care where the wind is from, it keeps its thrust and bending closer to normal. Under big sideslips, a tail rotor is positively screaming from the big stresses it develops. With the same maneuvers, the Fantail is calm as can be.
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ATSB now investigating!!!
albeit more difficult after the time lapse. i note the occurrence report refers to chtr. that may engender some awkward questions, Below A500 ft, extra pax and doing what appears as A/W?
I think we should reiterate that there is a second way to avoid the described LTE, other than buying the right helicopter, simply put the collective down, cyclic forward and fly away. duh!
Unfortunately when said collective is installed in said not the right helicopter which is said to be so close to said flora when the said TRFG departs the scene (LTE or otherwise), and when being flown by said pilot with 77 hours on type and 311 hours total, the said result will always be bent metal. As evidenced by everything said previously. Enough said.
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Well if BOTH pedals "go to the floor", then you're talking about a mech failure in the pitch control of the TR. Given that the pedals are linked - when one is forward the other is aft - it would take a catastrophic failure of the linkage to cause both pedals to go forward at once.
and when being flown by said pilot with 77 hours on type and 311 hours total, the said result will always be bent metal
when said collective is installed in said not the right helicopter
Di
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Well, the effect has been documented on a couple of machines...
I believe the naming evolution was:
'H*ghes Tail Spin', then 'Tail Rotor Stall', then 'LTE', after it was discovered that the tail rotor blades were still producing lift, albeit not enough....
I believe the naming evolution was:
'H*ghes Tail Spin', then 'Tail Rotor Stall', then 'LTE', after it was discovered that the tail rotor blades were still producing lift, albeit not enough....
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I have heard of a similar incident where the pilot experienced a sudden jolt and severe shaking with both pedals going to the floor
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Fixed Floats
These are fixed utility floats, not emergency pop outs.
They have no effect on cushioning the helicopter as the skids are underneath the floats.
4 pax on a hovering film job with turbulance! Thats a big no-no!
They have no effect on cushioning the helicopter as the skids are underneath the floats.
4 pax on a hovering film job with turbulance! Thats a big no-no!
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4 pax on a hovering film job with turbulance! Thats a big no-no!
especially if there is a lingering passenger liability claim in excess of the limited liabiltiy of charter coverage.
I know its cute to go for the chtr with its statuted limited passenger liability. But in reality I believe that CASA has a bit to answer for here as they have for the last few years been trying to push most of the airwork into a corner with the soiled washing and some blessed operators certificate type of system.
They also want to push everyone else up to charter (except parachutists IMHO) or indeed RPT where clearly the operation is only charter. This means that your average 311 hour pilot hasn't got a shmick as to which category that he is supposed to be flying in.
Once again though, that blighted simple single component which has caused more crashes than many other things, has reared its ugly head.