Maintenance, familiarity with our aircraft, "Startle Factor" & communication

[Live2Learn]

The heck of it is that "Distraction, and lack of familiarity..." can occur on the shop floor, with the Maintenance Officer's ignorance, and elsewhere.  I'm aware of at least a few instances where the MO failed to communicate maintenance discovered abnormalities that later turned into problems.  Absent communication (especially via Aircraft eDiscrepancies in WIMRS) potential problems remain invisible and unknown to the pilot who must later deal with the "Startle Factor" when an inflight emergency emerges.  This is the last of a four part video series, any one of which stands alone and is WELL worth a few minutes of time.

https://www.faa.gov/tv/?mediaid=1228  Chapter 4 ... the outcome of distraction or failure to communicate a known (to UMO) maintenance discovered abnormality... METAL in the oil. 

The video offers some very good suggestions for pilots to inoculate themselves against the "Startle Effect" when faced with problems created by upstream communication failures and maintenance issues.

I expect more than one of us can say "Been there, Done that!"

[NIN]

Circa 1987, Pyongtaek, ROK, I was a new Chinook crewchief on my first aircraft assignment after being trained.  My flight engineer was a new E-5 with an A&P and a "I know best" attitude about how he did aircraft maintenance (you can see where this is leading).

One evening after a night flight, I'm up top attaching the aft blade ropes when I note one of the blades is much, much lower than the other two on the aft head, literally scraping the tunnel cover on the top of the aircraft. Clearly it wasn't this way when we shut down (else there'd be a bigger mess) or did the post-flight, but something is amiss. My FE climbs up top and together we pick up the aft blade over our heads and hear a distinct "thunk" of the aft droop stop springing back in place at the rotor head end, putting that aft blade back in line.

"We'll take a look at that in the morning," my FE said. "I bet the droop stop springs are getting weak."

"Shouldn't we write it up tonight?"

"I already closed out the -12, so we'll just look at it in the morning" he said with a degree of finality.

I figured "Hey, he's the E-5, Mr. Airframe & Powerplant mechanic, I guess he knows what he's doing."

The next AM, we climbed up on the aft work platforms and spent a half hour replacing the springs on the aft rotor droop stop arms.  I went to write up the maintenance, but the FE told me we didn't need to do any paperwork, since we didn't replace anything that would ground the aircraft and it was too big of a pain the butt to get a tech inspector back out to the aircraft.  (all patently incorrect)

That night, I was assigned to fly a night flight with another FE on my aircraft.  As per the checklist when you're the guy "running the ramp" (performing duties in the aft of the aircraft), between the shutdown of the #1 & #2 engines, you check to ensure that the aft droop stops are indeed fully engaged. Failure to do so would cause one or more of the aft blades to collide with the fuselage as the rotor RPM slows and the blades "droop" (stop flying and flex).  Basically, the chances of destroying the aircraft are high when that happens.  Since its night, we use a flashlight to look at reflective markings on the droop stop arms to determine they are in the right spot.  Sure enough, I look, and one droop stop is out.

"Ready #2 to stop, chief?"

"Negative, sir... looks like we might have a droop stop out."

"Uhhhh, I'm going to bring #1 back up, chief."

"Fireguard posted, clear #1 to start."

We get both engines back online so we can work the checklist smoothly. The FE I'm flying with comes over and confirms that the droop stop is out of position.

A flurry of radio calls to company ops and I'm joined on the parking pad by the maintenance officer, the night contact maintenance team leader and our ops officer.  We spend about a half hour trying various combinations of control inputs as we take the engines in and out of ground idle with no change.  The fire department shows up, and after some minor language barrier issues, we explain that we need high-pressure water squirted right at the base of the rotor head while we run the aircraft up and down.

By the end of the whole thing, we were all soaked, the droop stop finally clicked back in, and my flight engineer got unceremoniously canned for performing maintenance without writing it up (and I got a nice healthy lesson in why you should treat superiors who are telling you to do things that are against your training, experience and knowledge of the rules with more than a big dose of skepticism).

This same sort of emergency happened to an aircrew at Fort Campbell in the mid-1980s, when a piece of the aft droop stop actually failed and fell off the aircraft while they were sitting at ground idle in hot gas. The crew chief panicked ["startle factor" perhaps?] and told the pilots "One and two to stop!" on the intercom.  As the blades wound down, one of the aft blades cut thru the tunnel covers and the #2 synchronizing driveshaft, destroying the aircraft . Ironically, sitting just a hundred yards away or so was a big gigantic "blade ramp" designed for just such an emergency. Push the ramp up alongside the aircraft and it would cause a drooped aft blade to "skip" over the fuselage.  But because this guy panicked and shouted to shut down before analyzing the situation, an $8M cargo helicopter was destroyed when it could have been saved for the cost of a replaced aft blade.

Startle factor, indeed.

[Live2Learn]

Circa 1987, Pyongtaek, ROK, I was a new Chinook crewchief on my first aircraft assignment after being trained.  My flight engineer was a new E-5 with an A&P and a "I know best" attitude about how he did aircraft maintenance (you can see where this is leading.
...

Startle factor, indeed.

You might say of the flight crew and mechanic should this have occurred in the field... "Flight crew DEAD, Mechanic...SAD"  Yeah, that'd startle the mechanic, sure nuff.

[Eclipse]

Holey smokes - something like this?









http://www.rcaf-arc.forces.gc.ca/en/flight-safety/article-template-flight-safety.page?doc=ch147204-chinook-epilogue-flight-safety-investigation-report/hl7ped67

And you're supposed to wheel this under spinning rotors?

That's terrifying!

[NIN]

Pretty much, yep