When I fly with someone new I often tell them my motto, "No paperwork, No News." That pretty much covers everything. Today I broke my motto.
I started my 4 day 24 hour trip with a 7:15AM report time.
It's a 3-2-4-3 trip. It was originally 19 hours but I added a 5 hour turn on the end. Christmas gifts to pay for.
The Captain I'm supposed to fly with got in late last night from another trip and was pulled off the first turn. The reserve Captain assigned to the trip is younger than me and just a little more senior. He was running late as he had a minor mechanical issue leaving an outstation. When he arrived I had everything set up. All he had to do was sign the release and review the logbook. I knew his name from when we were both First Officers on a previous aircraft.
We blocked out on time. I decided to fly the first leg.
Every modern jet uses a computer to control engine power settings. There's no direct connection between the thrust levers and the engines. Everything goes into a computer that decides how much power we get for a given thrust lever angle, stage of flight and aircraft configuration.
For example during takeoff, the computer uses outside temperature, pressure, aircraft weight and anti-ice settings to set a target N1 setting. The N1 is the front of the engine when viewed from the nose. When I'm flying I say "set thrust" and put the thrust levers in a defined detent. The Captain then verifies the power being produced matches the power being specified. If there is a discrepancy an aborted takeoff is considered.
During the takeoff roll when I'm flying, my eyes are outside and I never look at the interior screens until the nose is in the air. Once I hear "V1, Rotate!", my eyes go from outside to inside as my PFD is my primary instrument.
Today was normal during takeoff and climbout. I don't often look at the MFD or EICAS screens until we are out of the terminal area.
While passing FL350 I noticed the number 2 engine climb power being produced was not matching the climb power being commanded.
The FADEC was commanding 92% N1 power while the engine was only producing 90.5% power. I scanned down and noticed the ITT (Internal Turbine Temperature) was at the top of the normal range and the N2 (back of the engine so to speak) was at 100%.
"Hey something is up here." I told the Captain. I thought maybe I had moved the thrust lever for the number 2 engine back a little. I moved them back and forward....nope they were in the right spot.
The higher went the higher the ITT rose while the amount of power went down a bit. I pulled the thrust levers back and we discussed the situation. Something was definitely wrong with the Number 2 engine. The Number 1 engine was producing the correct power, had a ITT 100 degrees lower and had an N2 8% lower.
We were 110 miles south of an airport that has maintenance but just 200 miles north of our base. Since the engine was still making power and controllable we decided the safest course of action was to return to our base. The airport with maintenance was closer but had much shorter runways. Additionally we'd have to expedite down or get turned off as it was fairly close. Finally if we diverted there the passengers would be stuck till the next day as there were likely no spare aircraft available.
The Captain notified our dispatcher via ACARS then notified ATC. He handed the radios to me while he advised the Flight Attendant and passengers.
I told ATC we were not declaring an emergency just yet as things were controllable. He gave me a vector then assigned a RNAV arrival procedure. After the Captain was done with the Flight Attendant and passengers I told him what we were doing and mentioned it might be best to declare an emergency to avoid having to monitor the engine and deal with the step down fixes on the arrival. He agreed. Emergency declared and we were cleared direct to the airport vs a slightly complex RNAV arrival that had several level offs to deal with.
We began a slow descent. I used the VNAV to compute a descent rate that would require no level offs and would put me 5 miles from the airport at 1500 feet. It worked wonderfully. We did notice the lower we descended the more inline the engine parameters became.
An ILS to a visual approach were performed. I picked up the runway about 4 miles out. I saw several Fire Trucks and emergency vehicles along the runway.
After an amazingly smooth landing he took control and taxied off the runway. We then had a Fire Truck escort all the way to the gate as is normal in this situation.
Fireman lead came on board to see if we needed any help. Then several mechanics. Then a Chief Pilot. Just an hour later we had a new plane and were off again. Being so late I lost my overnight.
After we got back I had to fill out paperwork on the emergency.
A bonus is I get to watch Wreck It Ralph with my kiddo.
On another happy note I found the mythical Unicorn for next month. Day trips. More later this week.
It really seems like the fire truck response is overkill, but it's apparently required in the US because declaring an emergency is the full monty - internationally known as MAYDAY - meaning "grave and imminent danger" to the lives of all on-board. That is obviously not the situation you had - what you had is internationally known as "PAN-PAN" - a state of urgency, in this case due to the significant, but not gravely dangerous, mechanical problem.ReplyDelete
It would really make sense if the US adopted the international standard and distinguished between PAN-PAN and MAYDAY status, as it would allow for a more measured response in this situation - getting you the priority handling you needed but without everyone freaking out and sending fire trucks when nothing was on fire. It would also possibly reduce the paperwork as there wouldn't need to be as much justification/explanation for a PAN-PAN situation versus MAYDAY.
But I'm only Australian, what do we know...
We discussed the whole "declaring an emergency" and having fire trucks. We thought it was overkill, but felt it was best in case the other engine got worse or quit during the approach. We did elect to land with reduced flaps vs full flaps as to have lower thrust requirements on approach. Our operations manual states all emergency landings should be full flaps unless a checklist states otherwise. We used Captains authority to bypass that statement.ReplyDelete
Do you get to find out what was the cause of the engine fluctuations were, or do you just "hand the keys over" and walk away?ReplyDelete
Happy Christmas btw..