Monday, December 04, 2006

Return to Field

"Eighty Knots."

Caution and warning lights are extinguished, torque is set and steady, oil temps and pressures are looking good, and ITT is well under redline as our Megawhacker accelerates down Boise's Runway 28R.

"Vee One. Rotate."

The captain pulls back gently on the yoke and the machine lumbers into the early dawn sky.

"Positive Rate."

"Gear Up."

I reach for the gear handle on the instrument pnael, releasing the lock with my thumb and raising the handle with my palm in one practiced motion. The three yellow gear door lights illuminate, and the three green lights are replaced by red "gear unsafe" lights which go out one by one as each respective gear strut thumps into its wheelwell. Finally the yellow gear door lights go out as each gear door closes. Except for the right main. It's not going out. Hmm. It sometimes takes a few seconds, but never this long.

"Hey, check out the right main," I tell the captain. He glances where I'm pointing just in time to see the light extinguish, then come back on, and then cycle several times. A vibration accompanies each cycle, indicating that gear doors really are moving when they're not supposed to be.

"Hmm. Okay. Flaps up, climb power, after takeoff checklist," commands the captain, "and then run the appropriate emergency/abnormal checklist when you're ready. I'll keep it slow in the meantime."

The checklist runs us through a quick troubleshooting sequence that ends up telling us to put the gear down, leave it down, and keep the airspeed under 185 knots. Doesn't look like we're going to Seattle, I think. A quick call to maintenance control confirms that they'd like us to return to Boise.

A "return to field" is not in itself an emergency situation, but it is definately abnormal, with a higher workload than a normal arrival. The level of stress depends on the situation that precipitated the return to field, and how much time you have to complete the neccessary tasks. These pilots had just a few scant minutes to land the airplane before it burned up. In a non-emergency situation like our gear door, you can slow down or circle to give yourself more time and ease the workload.

The first step is communicating with Air Traffic Control. If it's not an emergency situation, you need to be clear about that; if they just hear "landing gear problem," they'll get a little excited. Tell them exactly what you want. Some delay vectors to give you time to run checklists and take care of other business can be a great help.

Next you have to communicate with company. Dispatch will want to know you're diverting. Station Ops needs to know to be ready for your return. Maintenance control will likely be involved in most returns to field. If they're playing "20 questions" with you at a critical time, be prepared to tell them you'll get back to them once you're on the ground.

Besides emergency/abnormal checklists, normal descent/approach/landing checklists need to be completed. The descent checklist can be easy to forget when you're already at pattern altitude, but you'll remember it when you land at a 3000' airport with a 500' cabin altitude!

You'll need to ensure you have adequate landing performance given current conditions. Dispatch calculated landing performance for your original destination, but you're not going there anymore. Make sure you're not over maximum landing weight - although in an emergency this is quite a secondary consideration.

Last but not least, you need to let the folks know what's going on. They'll notice you've turned around and are going back down, and are bound to be concerned. A long technical explanation isn't neccessary, but you don't want to be so vague that they're convinced the entire flight is doomed. If neccessary, brief your FAs on those details that are "unfit for public consumption."

And lastly, keep an eye on the other guy or gal. Mistakes are easy to make during periods of heightened stress, so you need to be watching each others' backs.

Our return to field turned out to be a no-brainer. We kept the plane slow, took time to communicate with everyone we had to, double-checked our work, and landed without further incident. Total flying time: 15 minutes. The problem was a broken uplock, which neccessitated a gear-down ferry flight back to PDX. Talk about the Slow Boat to China!

3 comments:

Anonymous said...

So, being familiar with the Megawhacker, and the fact that the landing gear is visible from the cabin windows, has it ever been done to ask the cabin crew (or go yourself) and vsually inspect an abnormal gear condition? To confirm that a gear has extended or has failed to retract?

And when you ferry an airplane gear-down, do you still fly at normal cruising altitudes, or do you take it low and slow so as not to damage the gear?

Norman

Sam Weigel said...

Yeah, if there was any doubt as to the position of the gear, we could have our FAs or a pilot sitting in the cabin inspect it. In the post-9/11 world I wouldn't count on anybody coming out of the cockpit to take a look.

There is no altitude restriction for flying the Megawhacker gear down, just a 15,000' limitation for operating the landing gear. We're limited to 215 kts with the gear extended, however.

Justin Rankin said...

Nice job man.

The guy who has a hanger next to us did a nice gear up landing on his beech bonanza.. Crazy

Thanks,
Justin (Mooney Airplane Dude) Renkin