Monday, August 01, 2005

The Twelve Minute Flight

At my company, we operate several triangle flights to cities that'd otherwise be too small to serve with any frequency. An example is Helena and Great Falls. Neither of these cities alone would be able to fill several aircraft to Seattle every day, but together they do. So we operate SEA-GTF-HLN-SEA. The middle leg is extremely short, since GTF and HLN are something like 56 nm from each other. A lot has to happen in that time, and you need to do some shrewed flying as well to make sure you're able to descend quickly enough after ATC keeps you high. One of my first legs on IOE was GTF-HLN. Fortunately I was the pilot flying - the PNF is the person who really has to work on these short legs. It was still pretty overwhelming.

Once you're comfortable with the airplane and familiar with the short legs, though, they can be pretty fun. It's airline flying distilled down to the interesting parts - takeoff, climb, descent, landing, with no hours of boredom in cruise involved. It's an exercise in efficiency.

Late last night, I flew the last leg of the day, the 57 miles between Bozeman and Butte. The weather was good VFR. Poor weather, while increasing the stress of the flight, gives you more time to think about it because you'll have to fly the departure procedure, fly further to the initial approach fix, slow down early for the approach, etc. In the short time from takeoff to touchdown, here's the tasks to be accomplished:

1. At 400', start climbing right turn on course. Keep up a steep climb at 200 kts so we can get to cruising altitude of 14,000 quickly. PNF retracts flaps at 1000'.
2. At 2500', PNF accomplishes after takeoff flow and checklist.
3. PNF checks in with Salt Lake Center; both pilots look for traffic that SLC points out.
4. PNF calls off times to Bozeman station.
5. In climb, both pilots reset airspeed and altitude bugs for landing, and set up nav radios for approach into BTM. PNF performs 10,000 foot flow.
6. Brief VOR/DME-A approach into Butte, with circle to Runway 15. Although the weather is good, the approach lets you get descend early so you're not caught insanely high.
7. Level at 14,000 feet. PNF gets Butte weather via ASOS. Accelerate to 280 kts.
8. PNF requests approach from Salt Lake, copies approach clearance and frequency change to CTAF. PNF reads descent checklist.
9. A few miles before Whitehall VOR, slow down in preparation for rapid descent. PNF performs early 10,000 foot flow. PNF makes in-range radio call to Butte station.
10. Crossing Whitehall, retard power levers to flight idle and begin descent to 9000'. PNF reads approach checklist.
11. A few miles past Whitehall, airport appears behind ridge. Call "Landing"; PNF reports position on CTAF.
12. Since it looks like it'll be tough to make the pattern altitude while going this fast, level off and have the PNF increase the condition levers for 1020 rpm. The extra drag helps you slow down to 200 kts, where you call for "Flaps 5, Gear Down, Landing Checklist."
13. PNF reads landing checklist. Aircraft rapidly descends to pattern altitude of 7100 as you cross midfield for the righthand downwind for Rwy 15.
14. Increase torque to maintain pattern altitude; keep wide enough to avoid 6400' hill just before turning base; call for Flaps 15, then Flaps 35 at 1000' AFE.
15. Stabilized approach at Vref by 500' AFE, touch down at exactly midnight, call it a night.

This flight reminds me of something my first flight instructor told me: - "Never take an airplane anywhere your brain hasn't been five minutes ago." My instrument instructor told me to always be thinking about the next three steps. Good advice on both counts.

5 Comments:

Blogger Lost Av8r said...

I did Vancouver to Victoria in 11 minutes today. 90% of the time we do this trip VFR so it's not so bad. The 1st couple of times I did the trip it was hard to keep up with my duties. Now I find I can get my stuff done in time to enjoy the view over the Gulf Island's. Even still, it's alot going on in a short period of time. Doesn't sound quite as busy as your trip though.

12:19 PM  
Anonymous Ron said...

Sounds like my typical IFR flight, only sans the extra pilot.

I like that aphorism about not going anywhere your brain hasn't been five minutes ago... can i steal that?? :)

7:13 PM  
Blogger Sam said...

Heh, I guess I should note that the flight I described is challenging for airline flying, but would be a yawner for the typical single-pilot freight dog or competent IFR PPL. The rest of the world has to do some serious multitasking; having two pilots makes it *so* much easier. Everytime I fly the Chieftain for AMF, I'm a little taken aback at how much there is to do at one time. It's good practice, though, because airline flying atrophies those skills.

6:21 AM  
Blogger Sam said...

Well it appears in several compilations of aviation quotes, so I'm guessing the saying didn't originate with my instructor. It's a good one, though, it's stuck with me ever since.

6:23 AM  
Anonymous Traytable said...

I'm guessing the cabin service on that leg is very short & sweet!! :p

1:55 AM  

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