Preventing Double Flameouts

[pelmet]

I remember this happening in flight to a Dash-8 on the east coast. Fortunately, they got one started fairly quickly. Remember, if you get a bunch of wet snow/slush, etc going into the intakes on the ground. It could then freeze and detach later on with anti-ice selection. Best to get a ladder to take a look inside, even if the plugs were installed overnight. Did it myself a few times.

It is not abnormal to see some ice in there that accumulated during flight but a large amount sitting on the bottom of the intake that could come off as a big chunk is bad news. In the Dash-8 case, the plug had blown out in strong winds and then been replaced later on so just make it a habit after a precipitation event where this could have happened.

"C-GPBR, an ATR72-202 aircraft operated by Calm Air, was conducting flight CAV503 from Thompson, MB (CYTH) to Gillam, MB (CYGX). While back-tracking for takeoff on Runway 06, the crew selected engine de-ice "ON" as indicated on the takeoff checklist. Within the following 5 seconds, the aircraft encountered a flameout and smoky shutdown of both engines (Pratt & Whitney Canada PW124B). The flight crew completed the engine shutdown procedure and brought the aircraft to a stop on the runway. The crew declared an emergency and the passengers were de-planed. ARFF responded and advised that no fire or smoke was evident.

Prior to the occurrence, the aircraft had been parked in blowing snow conditions for approximately 3 hours without the engine intake covers installed. Fuel quality checks were performed by the fuel supplier and the operator with no discrepancies noted. The aircraft fuel system inspection revealed no defects. The engines were inspected for damage from suspected snow/ice ingestion. Both engines were ground run and power checks did not reveal any discrepancies. The maintenance investigation is on-going."

[pelmet]

I have seen some aircraft manuals that suggest turning on the engine anti-ice/de-ice systems one at a time with a pause between selections when in moderate to severe icing conditions. I wonder if it might be a good idea anytime.


"C-GSAX a Summit Air Charters Dornier 228, was operating as flight SU1022 from Gahcho Kue
(CGK2), NT to Yellowknife (CYZF), NT with 2 flight crew and 6 passengers on board. The aircraft
had arrived from CYZF on an IFR flight in IMC with the engine inlet anti-ice on. After arriving, they
were on the ground for 10 to 15 minutes unloading and loading with the aircraft parked into wind.
There was blowing snow with the wind speed at 25 knots gusting to 30 knots. Once the
passengers were loaded the aircraft was started and taxied to the button of the runway. The
captain was not satisfied that he had sufficient runway visibility so he taxied back to the ramp and
faced into wind again to await the arrival of an IFR inbound aircraft. After 15 minutes had passed
the arriving aircraft landed and gave a pilot report that there was more than 1 mile visibility.
SU1022 then took position on the runway and departed CGK2 with the bleed air on, the propeller
and engine inlet anti-ice off and the engine ignition in the off position. At 400 feet AGL the power
was set to climb power and the propeller and engine inlet anti-ice were turned on in anticipation of
entering cloud at 700 feet AGL. As they passed 1000 feet AGL and commenced a turn towards
CYZF, both engines (Garrett TPE331-5-252D) flamed out. The captain cycled the power levers
back and forth and was about to feather the propellers in preparation to glide back to the field when
he noticed that the engines still had temperature and oil pressure. He switched the manual ignition
on and both engines relit. With engines parameters stabilized the crew elected to proceed to the
destination and landed without further incident.

Maintenance update: Both engines were bore scoped for damage and none was found. All
systems were checked and verified operational. An engine check run was completed with all
systems functioning normally and the aircraft was returned to service.

Operations Update: In consultation with the engine manufacturer (Honeywell) and the airframe
manufacturer (Ruag), Summit Air Charters has updated their Dornier 228 SOPs and checklists in
regards to the definition of icing conditions. The updates apply to when the application of engine
inlet heat and propeller heat occurs as well as when the ignitors are turned on and how long the
ignitors remain on."

[goldeneagle]

How can you start a thread on dual flameouts, and not mention Romeo Oscar Mike? MU2 in heavy ice with a dual flameout, episode started in the vicinity of Revelstoke.

Part 1
https://www.youtube.com/watch?v=Wbm8xzLVgQ4

Part 2
https://www.youtube.com/watch?v=_lAu-HpzqM4

[Commonwealth]

How can you start a thread on dual flameouts, and not mention Romeo Oscar Mike? MU2 in heavy ice with a dual flameout, episode started in the vicinity of Revelstoke.

That was like watching a Hollywood movie. I almost cheered at the end.

[Canoehead]

Air Nova had a couple with the Dash 8 years ago. One out of YQY and I thought there was another out of YYT or YDF but I can't find it right now.

There's been a mod done to the intakes to help prevent this as well as new SOPs for the Dash 8 in terms of checking intakes. To my knowledge there's been no incidents since.

https://www.bst.gc.ca/ENG/rapports-repo ... a0030.html

[pelmet]

I am a bit puzzled as to what happened with the Dornier. I would assume that it was quite cold outside and just blowing snow. Typically, it is chunks of ice that cause this problem which usually is not something an aircraft has accumulated in the -30 degree world. And with engines running on the ground for a while, I am not sure how any thing would have accumulated. Any accumulation on the ground prior to engine start would just be powder snow.

[Edelweiss air]

Nicely done by the Dornier crew. However, dual flame out and then continue on to destination after ??

[Commonwealth]

Nicely done by the Dornier crew. However, dual flame out and then continue on to destination after ??

Returning to the point of departure which in this case had a raging blizzard may not have been the safest course of action.

[VSF]

I am a bit puzzled as to what happened with the Dornier. I would assume that it was quite cold outside and just blowing snow. Typically, it is chunks of ice that cause this problem which usually is not something an aircraft has accumulated in the -30 degree world. And with engines running on the ground for a while, I am not sure how any thing would have accumulated. Any accumulation on the ground prior to engine start would just be powder snow.

On upside-down Garretts (Intake on top - like the Metro), snow has a habit of melting and then refreezing in the intake. There was even a convenient little pocket for the water to pool in. I'm surprised it didn't all just drain out on the Dornier. Perhaps the wind blowing into the intakes packed some snow in there, which then froze to the side of the intake. It would only have been dislodged when the intake heat was turned on...

When I flew Metros, it was company policy to put the intake plugs in any time it was snowing, regardless of the length of the stop. Interestingly, the general practice was to never perform a takeoff with the intake heats on, and then to turn them on after departure - exactly like this incident. I'm not sure why that was, as the performance charts/WAT charts, and AFM allow and require you to depart with the heat on in "icing conditions".