REFLECTOR: N21HV Engine starts (or "No Shoddy Work Goes Unpunished")

[Scott Derrick]

Nice story Hiroo, I've had a 100LL flood myself, different leak source. 
Its definitely a stressful situation.

Glad all turned out for the better.

I am envious of that first start event though.... Someday...

Scott

Hiroo Umeno wrote:
>
> Short Summary:
>
> At 12:30pm on August 1st, my plane “N21HV” made its first “airplane 
> noise” without my vocal assistance.
>
> Details:
>
> 8/1 was to be “the big day” as the DAR was scheduled to pay a visit at 
> 1 for final inspection and issuance of the provisional airworthiness 
> certificate. Steve Murphree flew in (commercially) from Reno for final 
> factory approved inspection and flight testing. We spent all morning 
> going over the plane in minute details and he was satisfied with the 
> workmanship and the general condition of the plane. Steve had a few 
> improvements suggestions but nothing that precluded us from flying the 
> aircraft safely. I was quite satisfied to know that all the critical 
> measurements were well within the factory specified spec.
>
> We broke for lunch and gathered around the plane around 12:30. At this 
> point, one thing we have not done was to actually “light the fire”. We 
> had 30 minutes or so before the DAR showed up so we looked at each 
> other and said “Let’s fire it up!”.
>
> With Steve, the test pilot, at the controls and two mechanics kneeling 
> about 20 feet away on both side abeam the engine with fire 
> extinguishers, and me behind the camera, the electrical fuel pump was 
> turned on for a few seconds, followed by the starter. Steve had to 
> pump the throttle a couple times but then, just like magic, the plane 
> started making “airplane noises” on its own. About 1 minute into the 
> engine run, the two mechanics spotted dripping below the speed brake 
> and waved off. As Steve secured the plane, we saw that what started 
> out as drip-drop, quickly developed into a waterfall of fuel gushing 
> from the cabin floor. After making sure there was no ignition source, 
> I ran to the airplane and pulled on the fuel-cutoff which did not have 
> any effect. We climbed in and manually clamped off fuel lines from 
> both strake tanks as we were certain the problem was after the tanks. 
> By this time, the cockpit floor on the pilot side had about ½” of 
> 100LL. We placed a bucket below the plane to capture the fuel, which 
> was about 1 gallon in it by now.
>
> In the middle of all the excitement, the DAR showed up. Not the best 
> time to “inspect” the plane… He was really good natured about it, 
> though. Something about “we call these things ‘experimental’, right?”
>
> We had to drill a small hole on the floor above the speed brake (air 
> drill of course) to drain the puddle on the floor, and then evaporated 
> much of the remaining fuel using the compressed air blower. It’s 
> amazing how fast fuel evaporates.
>
> We pulled the header tank and discovered the source of the problem. 
> The header tank is constructed from two pieces of pre-molded 
> fiberglass parts. It was one of the earliest fiberglass layup I had 
> done (before I had consistent working procedures). There were areas 
> where the glass did not cover the joint and was held by resin alone. 
> Amazingly, this has held all this time through multiple fill – drain 
> cycles, pressure testing, leak testing, etc. However, running the 
> engine has introduced another element into the equation in the form of 
> vibration. This cracked the weak joint in a matter of 50 seconds or so 
> resulting in fuel being dumped into the cockpit. Since the fuel 
> shutoff comes after the header tank, it had no effect.
>
> The good news here is that we found the problem on the ground very 
> quickly, root caused and remedy being applied. The engine ran a bit 
> rough but I am guessing that it will smooth out as it breaks in (it is 
> a fresh 0 timed engine).
>
> A day and a half later, the sump is now repaired and I am planning on 
> doing another starts Friday morning.
>
> Hiroo
>
> ------------------------------------------------------------------------
>
> _______________________________________________
> To change your email address, visit http://www.tvbf.org/mailman/listinfo/reflector
>
> Visit the gallery!  www.tvbf.org/gallery
> user:pw = tvbf:jamaicangoose
> Check new archives: www.tvbf.org/pipermail
> Check old archives: http://www.tvbf.org/archives/velocity/maillist.html

-- 

-
    Truth : the most deadly weapon ever discovered by humanity. Capable of destroying entire perceptual sets, cultures, and realities. Outlawed by all governments everywhere. Possession is normally punishable by death.

    Richard Childers