Aircraft Type – Swearingen Metro
Location – Wellington, NZ.

MAYDAY!… MAYDAY!… MAYDAY!… WELLINGTON CONTROL, METROLINER LIFEFLIGHT

ZERO TWO, RIGHT ENGINE FIRE INDICATION, REQUEST PRIORITY DESCENT TO WELLINGTON…”

Our flight originated from Auckland International on a medical mission to Wellington to collect a patient experiencing difficulties during pregnancy, from memory. The callout was generated on a Saturday evening just after dinner time & required the carriage of a Doctor, Flight Nurse & Crew Chief excluding myself & the Captain.

Our Crew Chief for this evenings’ flight was relatively new to our operation & I’d flown with him on a few occasions since his induction training. He, like myself was also a ‘fling-wing’ pilot & unlike myself was working this job as a part timer.

Now most pilots will probably not admit to being a little superstitious, but I’ve witnessed & been told by older pilots to always place your cash notes the right way up & in order of denomination in your wallet (don’t quite know what relevance it has to aviation, but there you go…) & have myself been a little guilty of doing things such as selecting phrases so as to not to place a ‘hoodoo’ on anything (what I called the ‘Boogalahs’ in my previous life as a carpet layer). Anywho… Whenever this particular Crew Chief & I are flying together, there always seems to be an event of some sort, whether it be a loss of pressurisation or a malfunctioning instrument in flight or some bizarre weather event on approach… something always happens! This night was no exception…

The Captain & I briefed each other regarding the flight, expected conditions enroute,
contingencies, fuel requirements etc. etc. There were no particularly pertinent NOTAMs & the weather was typical for the time of year with no forecast turbulence or icing & no CBs & visual conditions on approach to Wellies so all in all, just a standard mission to complete.

The aircraft preflight was checked out sweet & we met our crew for the evenings flight. The Crew Chief & I had a little chuckle when we met each other & wondered what was going to transpire this time round. Checks & giggles aside, loaded up… Time to light the fires.

Airborne, Control asked if we required priority, so we guessed that the airspace was due to get a little busy the further south we flew. “Negative priority this sector Control… Lifeflight 02…”

Cruise altitude for this sector was FL160, the wx was fine, Auto Pirate engaged & we
settled in for the one & a quarter odd hour flight. The cockpit banter was light & when I checked in to the cabin via intercom, the Doc & Nurse were quietly discussing their patient & their procedures as to the most appropriate care on the return sector. I think the Crew Chief was listening to music, so he was pretty much relaxed after having ensured the cabin was secure for the flight. I commented to the Captain that the night was unusually dark for that particular time. He agreed & we continued on with our duties as he called for the cruise checks.

Further on, we got the latest ATIS & started to discuss the approach. Nothing untoward & expecting visual conditions below about 2000 feet, so position for the ILS initially… No dramas. No wx was painting on the weather radar (as was expected), but again I mentioned how dark the sky was. This time the Captain leaned forward a little to take a peek out the forward windscreen in an effort to further reduce any glare from the cockpit instruments. Normally we would see some stars & he commented on that. Still, no big deal & we carried on ‘ops normal’.

I checked in with the cabin to give the Crew Chief an ETA so he could co-ordinate with Wellington Free Ambulance to meet the aircraft on arrival & even he commented on how dark the sky was. I asked if he could see a faint orange glow from the starboard engine exhaust from his crew position, but on this occasion he “couldn’t see jack!”. With this I asked “Hey Skipper… Turn the wing leading edge light on for a sec”. We use this light to check the leading edge for any ice accumulation. “You got the light on yet?” I asked, to which he replied in the affirmative… “Man, I can’t see anything… Bloody side pane must be dirtier than usual” I said with a chuckle. As I returned my gaze forward, I noticed St Elmo’s Fire on the Co’s heated windscreen, which I mentioned to the Skipper.

Now, I think St Elmo’s Fire looks pretty awesome, but in order for it to appear it has to have some sort of catalyst. I’ve only experienced it prior to or during a series of thunderstorms in the vicinity of the aircraft. Due to there being no adverse wx forecast along with the general trend not conducive to bad wx & nothing on the radar, this was particularly weird. The ‘Boogalah’ of the Crew Chief & my pairing strikes again!…

St Elmo’s Fire in a Metro is probably more concerning, as it closely resembles electrical arcing & I’ve experienced a shattered windscreen on the Captains side following such a display. You see, the Metro has a peculiar windshield heating system & doesn’t like too many outside interferences such as static electricity build ups. Armed with all things considered (or so I thought) & experience, we put these occurrences down to ‘gremlins’.

Further along the flight & just prior to top of descent, we were handed off to Wellington Control… “Wellington Control, Lifeflight Zero Two maintaining FL160, weather blah, blah, blah…”. Control replied giving us the appropriate Standard Arrival. A minute or two later, Control broadcast a new SIGMET that stated ash cloud between an area South of Mt Cook to Stewart Island in the far south, which didn’t concern us geographically because our destination was some 2-300 clicks away to the north of the phenomenon. The Controller finished reading the SIGMET in their usual ‘matter of fact’ way. I keyed the mike following other transmissions to acknowledge receipt… “Lifeflight 02″…

By the sounds of the other acknowledgements, all other aircrews in our airspace were thinking the same thing… What caused this ash cloud down there?… Did Mt Cook awaken & spit the dummie? I quizzed the Captain, but he didn’t know so I called the cabin to ask the Crew Chief whether he or the medical staff had heard anything on the news regarding volcanic activity in the south island to which they all replied in the negative.

The conversation in the aircraft was quite animated now with conjecture as to this strange SIGMET. Now, in case you’re wondering why we didn’t just call Control to query the origin of the ash cloud, the radio silence following the broadcast indicated that all other airborne crews were obviously having the same animated discussions as we were while waiting for
someone to grow some kahuna’s & ask… Mine remained in their prune like state… It had been probably a minute since the SIGMET.

“BBBBBBBBBRRRRRRRRRRIIIIIIIIIIINNNNNNNNNNNNNGGGGGGGGGGG!!!!!!!”…
What the???…… Jesus!!!… “Skipper, we’ve got a right engine fire indication!”… I looked out my side & couldn’t see any flames, but then I remembered I couldn’t see anything out there before anyway… “I can’t see any evidence of a fire out my window Boss!”… I looked at the Captain expecting him to ask for the recall actions, but the initial look of horror on his face while looking at the annunciatior panel with all its’ red lights going along with the right engine fire light illuminated & the blaring of the claxton told me what he was thinking in that instant… ‘I CAN’T believe this is f#*kn’ happening!’…

“SKIPPER!…” I called louder & about three octaves higher. My kahuna’s now disgracing me by shriveling to the size of raisins … “WE HAVE A RIGHT ENGINE FIRE INDICATION BUT I CAN’T SEE EVIDENCE OF FLAMES OUT MY SIDE… ARE YOU READY FOR ME TO CARRY OUT RECALL ACTIONS!?”…

This shook him from his state of momentary shock. He called… “CONFIRM RIGHT
ENGINE FIRE INDICATION”… I replied as per SOPs… “RIGHT ENGINE FIRE
INDICATION CONFIRMED”

In accordance with our emergency checklist the AP was disengaged, the right engine was shut down & the extinguisher fired. I talked to the cabin & advised of the situation. There was stunned silence, but I could hear the Crew Chief beginning his appropriate cabin checks…

“MAYDAY!… MAYDAY!… MAYDAY!… WELLINGTON CONTROL, METROLINER LIFEFLIGHT ZERO TWO, RIGHT ENGINE FIRE INDICATION, REQUEST PRIORITY DESCENT TO WELLINGTON…”

This all occurred within maybe 90 seconds.

WN Ctrl, cool as a cucumber…
“Lifeflight 02, Control. Copy your Mayday. Descend your discretion to 8000 feet Radar Terrain, track direct WN VOR. When available Sir, Souls on board & confirm you are operating asymmetric”

Me, not so cool… “Descend to 8000 Radar Terrain, direct WN VOR. 5 on board & we have shut down the right engine due to right engine fire indication. There appears to be no physical evidence of a fire & could be an instrumentation glitch, but regardless have shut down the right engine. Mayday Lifeflight 02”

WN…
“Lifeflight 02 understood. We have full emergency services turnout & tower advises weather suitable for straight in approach from the north. Expect vectors closer in for a centerline approach Runway 16. Descend now to 5000 feet”

After reading back the new clearance, the Skipper gave a brief on the abnormal
procedures approach & asked me to talk to the cabin.

The cabin was not so silent by now! The Doc was freakn’ out a little, so I tried to emulate the ‘cool as a cucumber’ controller. In my best act of ‘Co-Pilot Cool’, I told them that we had a right engine fire indication & that it was procedure to shut it down. I asked the Crew Chief if he saw anything abnormal out the right side of the aircraft, as his crew position is next to the exhaust but facing aft. He said that there was no sign of abnormalities. The only abnormality was hearing the alarms go, the engine going quiet followed by a girlie sounding Co saying he had to shut down the engine due an alarm! So my jig was up! The Crew Chiefs frivolity had taken the edge off & we all had a little chuckle.

I asked him to prepare the cabin for a possible emergency landing because it was still in the back of my mind that we hadn’t confirmed that we hadn’t actually had a fire. The Crew Chief told me that he had already done so. All our Crew Chiefs are highly trained on this aircraft type & would’ve handled the situation just as admirably. Just saying…

We broke out of cloud at around 2500 feet in crystal clear visibility & right where the
controller said he would place us. This was my first opportunity to be able to see out my side to the engine now feathered & useless. Were those black streaks running down the side of the cowling? Don’t know. Maybe I’m imagining it.

I looked forward & the Skipper exclaimed “Geez mate, look at that” as he gestured
forward. Ahead of us was the runway & down one side of it there were red & white flashing lights of the fire rescue vehicles which we were expecting, but we weren’t expecting to see a queue of Wellington traffic on either side of the runway threshold held back by red & blue lights of not one, but several police cars with black nothingness in the dark night in between. We looked to the far end threshold & there was a repeat ensemble of police lights while between them was darkness. The police had effectively blocked off traffic on our approach path & also our go around path… There would be no go around tonight!

Tower cleared us to land & at the request of fire rescue, wanted us to remain on the runway so they may inspect (or otherwise) the affected engine. Upon their initial inspection they determined that there was no sign of fire, so we were cleared off the runway for shut down & closer inspection.

A full investigation was carried out & it was determined that either a faulty resistor or
capacitor had actually fired the extinguisher bottle, which in turn instantly set the fire
indication off. What was still a mystery however, was what caused the electrical surge to fault the resistor or capacitor. Could it have been arcing in the windscreen? Or was it actually St Elmo’s Fire that we witnessed & if so, what was causing that? As I’ve already alluded to, there has to be some catalyst for that to occur.

Now, we were still perplexed by the unusual darkness of that night which we reported
along with the St Elmo’s Fire as part of the investigation. No one could give a definite
reason to this, but remember the SIGMET that was issued in the South Island & well away from our track?

The source of that ash cloud was from a volcanoe in Chile which went on to disrupt many flights affecting many southern hemisphere countries as you probably know now. At the time, it had not even registered (with me at least & I’m sure the other aircraft airborne that night) that the cloud had actually encircled the entire southern part of our planet. After all, we are subject to predominantly westerly windflow, hence the SIGMET stating ‘from Mt Cook to Stewart Island’ made us immediately think of no other possibility but a new source in the south island (couldn’t possibly be from Chile in the East). Apparently there was no ash cloud in our vicinity that could have caused the dark night or the St Elmo’s Fire… But something caused that resistor or capacitor to blow the extinguisher…

Oh that’s right… It was the “Boogalah’s”…