Gyro Accident Tasmania

[Tim]

Murray or Mitch, tell Al that the fishing would have been better back home if he really wanted to do that. There must be a joke in there somewhere about 2-strokes and marine anchors.Any sign of the gyro yet?

[asra]

Hi All, we have just got back from another search. 3 hours of dragging a grappling hook over the back of a charter boat. We have some sonar positions and are putting a diver in in the morning. After many years of attending ASRA Nats this is the first time we have spent more time in a boat than a gyro.Allan would like to know if Russ will volunteer to be towed behind a boat attached to a besser block.

[Russell]

No probs..........as long as you is there with me

[GraemeMonro]

Allan receiving his prizes and trophies at the nats.

[Disco]

Allan would like to know if Russ will volunteer to be towed behind a boat attached to a besser block.I"d take that job if i was there.

[Greg Mitchell]

G"Day Fellas,Allan is going to write a report on his visit to Tassie upon returning home early next week. The life saving floatation devices may come in handy as his beloved Sunshine Coast is inundated with water. (Thanks Niel ;D ;D ;D)A third attempt at reading the bottom of the Tamar is likely to be effected using a Hummingbird Depth Sounder capable of producing 3D images with a 45 meter sweep of the the bottom. Alledgedly it can locate fishing rods and reels. The recovery of outboard motors is the norm.

[Disco]

In the interim both remaining Butterfly Monarchs are being modified to incorporate safety straps linking

[Greg Mitchell]

G"Day Dean,At this stage a broken rod end is mere speculation and one of a couple of possibilities.There was a loss of control of the aircraft. There are some who already have redundant straps in place.The US forum has a thread running re same.Allan, Murray and others,

[asra]

I will clarify my thinking on this subject. Butterfly gyros come from the factory with high quality aviation type rod ends but Allans were replaced after the rollover a few years back with non aircraft brand.This type is being used in many types of gyro throughout OZ.They are 5/16 size,gold cad plated with hard plastic inserts.One day whilst preflighting the "Hunchback" I found a rod end snapped off,and the opposite side bent!Further investigation found that the control bottom rod ends may have been touching(binding) slightly with full control movements.They were 5/16.I also think with some of today"s high powered prerotators it will put added strain on all control components.Any bad flapping/hinging incident I would also replace ALL rod ends.I will either be using 3/8 rod ends in future or on any existing models (with 5/16) I own or repair modify with 1/16 stainless wire safety retainers.

[hatrack]

My little 503 has 3/8" rod ends. Are 5/16" more common? Go buy a Lotto ticket Waddles!

[Disco]

One day whilst preflighting the "Hunchback" I found a rod end snapped off,and the opposite side bent!Further investigation found that the control bottom rod ends may have been touching(binding) slightly with full control movements.They were 5/16.Wow, That"s amazing.

[Tim]

I think that it would be wrong to speculate as to the cause of Allan’s control failure at this point of time. It could cause unnecessary concern, and could lead to unwarranted modifications, which if not correctly carried out, could conceivably create further problems where none previously existed. If any modifications are done ‘just in case’, they should be thoroughly checked out by an ASRA T/A. The control failure could easily have been caused by a failure in the complex pre-rotator system, a bird strike, some degree of airframe failure, a failure in any part of the control system (or rotor head), or simply human error (of which we have all been guilty of).We should know the exact cause once the gyroplane has been recovered, and things are looking very favorable for a recovery shortly.. Several examples of the 5/16” commercial rod-ends previously mentioned have been tensile tested to failure. Failure occurred in the loop around the ball, and that happened at just over one ton. We did not test them in compression but given their construction and their most common mode of operation, failure in compression could be considered to be out of the question. We also bent them at right angles without failure, but they did fail after a few bends backwards and forwards. I do not recall one instance of installed failure in this type of rod end that hadn’t suffered previous stress, and such rod-ends are the most common in use in Australia today, with many hundreds of thousands of hours.A 5/16” X ¼” aircraft rod end put through the same tests as above, failed at lesser standards. The threaded shank failed first in tension and the shank also failed when bent. However to be fair to the aircraft rod-end, the shank was hollow (manufactured that way), and it was second hand (normal time expired replacement, but appeared to be in perfect condition). I could not afford to test a new aircraft rod-end. It is interesting to note that one Gyroplane manufacturer in Australia used ¼” rod ends.

[Mark Horan]

That"d be the Skyhook? ???

[Tim]

The JRM Heliplane Mark. Did the Skyhook also have 1/4" rod ends??

[asra]

On the subject of rod ends The standard 5/16 would have clocked up countless hours mustering. At the same time I once bought some grade eight bolts where every second bolt was faulty. Although they looked perfect they sheared off at the head or the start of the thread under very light tension. When the supplier checked the rest of the box were the same. It might"nt hurt when replacing rod ends to buy a couple of extra from the same batch and give them a bend in the vice.Peter.