Announcement

Collapse
No announcement yet.

Monarch Rollover

Collapse
X
 
  • Filter
  • Time
  • Show
Clear All
new posts

  • Monarch Rollover

    Gidday All,Circumstances of late have precluded an earlier post regarding this accident. My humble apologies.I had received the upgrade kit for the "G-Force" landing gear, and with the help of Murray, fitted it in about 4 hours. After the necessary photos and paperwork were complete, I set about taxy and eventually flight tests.The taxi tests revealled that the new gear did not appear to have the same shock absorbing capability as that of the original gear, most probably because the new gear is designed to handle severe vertical loads, not accommodate rough ground. However, being used to the suspension or lack thereof on the RAF, it was different, but not uncomfortable. The wider wheel track slightly improved the lateral stability on the ground.Takeoff was normal, with no indication that the gear actually dropped a couple of feet as the weight transferred to the rotors. Inflight handling and performance was not appreciably affected. The first landing was strange. A higher than normal flare was initiated and a smooth touchdown ensued. The feeling was weird. Not fully on the ground, and not fully in the air!! It was a gentle letdown if that's the term. Second landing, I decided to touchdown and apply some back stick to shorten the ground roll. In the application of back stick, I obviously biassed it the the right, being right-handed, and a roll in that direction ensued. Manageable by all means, but unexpected. The wait until the gear bottomed out seemed long. I theorised that in applying back stick after touchdown it actually increased the lift, which prolonged the time it took for the gear to bottom out. Fix? Pole forward to a level attitude on touchdown therefore dumping some rotor lift and transferring the weight to the gear which should then let down a bit quicker. The execution appeared to go well, except that the nose appeared to drop more than I expected, and the next I knew was that I was on my side on the ground with the dust settling. Bugger.Murray was there in a flash as was the Airport Safety Officer. No significant damage to me, but not so the Monarch. We lifted her onto the gear and pushed her to the hangar, recovering the nose wheel in the process. Murray confrimed that the touchdown had definitely been on the mains, but everything happened so quick after that, that detailed recall was not possible.The ASRA Accident report Form F 002 states:Probable cause: Pilot error.Possible Contributing Factors: Rough ground and welding failure in the nose strut.Photos of the failure of the strut were sent to Mitch and Larry Neal. Several opinions were sought from qualified welders as well. The consensus from these gentlemen was that the welding was defective. It appeared to have been completed with a MIG process during which the parent metal had been burnt through leaving a crystalline filler material to complete the join.Mitch confirmed that this particular leg was the only one of it's type to be imported into OZ. All others are manufactured locally from material with a greater wall thickness and TIG is used in the process. Mitch is in the process of having test welds done for destructive testing.My immediate problem was to get a machine ready for the Nationals, this being only 10 days before planned departure. As luck would have it, a friend had a basic Monarch kit not 20 minutes drive from me. He immediately offered whatever components were necessary to effect the repairs. Thanks David. Murray and I completed 90% of the rebuild in a day, the wiring and tidying taking a couple of extra part-time days. Something else precluded a speedier completion. At no stage did I approach Mitch or Larry for compensation or consideration for what appeared to be a manufacturing fault. I still don't know. From the Accident Report, I wear the can and I have no intention of changing that. Mitch immediately agreed to replace David's kit parts for exchange at Cooma. This was effected. In the interim, Larry advised that I was not to be charged for the components that needed changing. This was totally unexpected and not in line with what I had been led to believe happened with manufacturers and TEST PILOTS. Larry is a genuinely good bloke, and has subsequently opted to change the nose wheel design to something similar to that which Murray made for me. This guy understands R & D, and is prepared to accept that field operations will reveal defects that he is willing and prepared to address.So. The statement in another thread on this forum that "Larry Neal had to replace...." is BS. I wonder if the manufacturer of the elusive FIREBIRD has the same ethics?Regards,Waddles.
    Waddles

    In aviation, the only stupid question is the one you don't ask!

  • #2
    Gidday Gents,Good post Allan, just wanted to clarify a few points.Allan Wardill tried hard to carry this incident/accident on his own shoulders by posting as Pilot Error. This gives you an indication of the sort of bloke he is. A front strut failure is hardly pilot error.The R & D on the single front strut for Butterfly and then Monarch were all done on 58 thou chrome molly with single spring. Even during a year of testing various GFLG set-ups, Larry used these same strut configurations with no failures. He found he needed more sprung front end to assist GFLG with soaking up the vertical impacts and went to a three spring front strut and to ensure a greater degree of safety went to a 124 thou wall thickness chrome molly.The 58 thou wall thickness strut with single spring is for Butterfly only. To clarify, local Oz struts are 58 thou with a heavy wall thickness axle (this was all I could get at the time through BIT, Race Tech) This was how we were able to identify point of origin. I had sent Allan a US product because I wanted first to run the Oz product on my Butterfly. We should have ensured Allan's Monarch was fitted with the beefed up version. I was mortified when I got the call re this accident and immeadiately enquiries were made as to history of operations and prototype testing.To cut a long story short the strut in question was defective (some believe it was mig not tig) and from all accounts failed under normal loads not GFLG type drop ins. Larry is reviewing his welders processess as am I.Both Larry and myself are installing Murray Barker type front ends from this point on, in Butterfly/Monarch craft. Everybody moved quickly to assist Allan with what was required to get him airborne and to Cooma. Many thanks to David "DAJ" for making parts available, to Allan's friends/team in Qld and to Larry Neal who very quickly offered his support and effectively making R & D changes to all front struts for this range of craft.Further Tig welding processes have been adapted accordingly to ensure future components meet/or and exceed expectations.Chrome plating of the heat treated 4130 components will be deleted due to possible exacerbation of hydrogen embrittlement and argon gas will be pumped into welded components to expell oxygen, reducing the likelyhood of embrittlement occurring during the tig welding. I wish to publicly thank Allan Wardill for his passion and enthusiasm, his dedication as Opps Mgr to the ASRA and the membership.And for being there for me, from the start.Regards,Mitch.www.thebutterflyllc.com

    Comment

    Working...
    X