Dec 10, 2007

A Day in the Life (30) InRange

A description of a typical day's flight from Montreal to Vancouver and return - as a backdrop for a detailed, non-technical description of what an airline pilot does. (check left hand column for series index).

Log Entry 2003 - A320 Capt - Descent

Time: CYVR Arrival minus 0H10


“In Range Check,” she calls…

I quickly work my way across the flight panels, activating the key switches, including the landing lights and seat belt sign. A quick check that our instruments are set for the upcoming approach mode, and the desired screens are displayed. I confirm the automatic braking is selected according to F/O Paula’s earlier briefing. And finally I double check that our navigation genies are giving us accurate information. The finest electronic moving map displays become dangerously misleading if they aren’t anchored to reality by appropriate raw data. So I ensure that the DME distances agree with the computed distances to Vancouver.

Finally I pull out the printed card and read the list out loud:

IN RANGE CHECKLIST
– "LIGHTS ...................................................................."ON"
– "SEAT BELTS" ........................................................"ON"
– "LANDING DATA"......................................................"SET"
– "AUTOBRAKE ........................................................... "LOW "
– "NAV ACCURACY"....................................................."CHECKED"
"IN RANGE CHECKLIST COMPLETE "

F/O Paula begins slowing down to 250 knots as we approach the ten thousand foot level. There are no highway signs posted, but that's the speed limit. And reducing airspeed is one of the few ways we have to stretch time when things get busy.

She already has the speed brakes fully deployed. The next strategy on the list of ways to slow down is to reduce the descent rate. Which she doesn’t really want to do because we’re already above the ideal descent angle and this will only make that problem worse.

Most people think that small airplanes glide better than the big ones, but this is generally just the opposite. Airliners are so aerodynamically efficient that extra drag is needed to allow us to descend sharply without picking up speed. The “go down - slow down” issue is often a problem for jet transports. So we are equipped with speed brake panels on top of the wings that rotate upwards into the airflow to produce drag.

http://en.wikipedia.org/wiki/Spoiler_%28aeronautics%29http://en.wikipedia.org/wiki/Spoiler_%28aeronautics%29

We both glance out the window to see if any ice is accumulating on our ice detector system, which is the nut on the base of the windshield wiper. It’s nice to know that some things haven’t changed on the elctro-bus. This is still the most reliable and cost effective way to detect airframe icing just as it was thirty years ago on the 727s and DC9s.

“We’re getting rime ice,” I tell her. I check the outside air temperature. It's just below the freezing mark and the clouds are getting really juicy. And our exterior airframe is a huge cold-soaked metallic ice-making machine after the spending the last five hours at minus fifty degrees at altitude. F/O Paula reluctantly calls for airframe anti-icing, which I switch on. Much to her chagrin because this added demand on the bleed air, automatically increases the engine rpms adding yet more unwanted thrust to the equation.

“GooseAir 111,” Vancouver Arrival calls, “Reduce speed to 210 knots.”

Things are really piling up, conspiring against F/O Paula's best-laid plans. The required altitude fix on our nav screens is now showing amber, telling us what we’d already figured out. We can’t make that restriction at this reduced airspeed, especially with all the anti-icing equipment running.

Time: CYVR Arrival minus 0H06

1 comment:

Soaring Student said...

Drop the landing gear!!!!!

This is an awesome series of posts, which I am enjoying thoroughly. Thank you.