More Information‎ > ‎Newsletters‎ > ‎

Aviation Safety

AVIATION SAFETY

Dave Fry, WVFC CFI and Aviation Safety Counselor dgfry@aol.com


The Best Laid Plans

We all know that when you’re flying IFR, there are three flight plans involved: the one you plan and file, the one you’re cleared for, and the one you actually fly.  Only a fool would believe they’d be same.  Mostly we think of the differences as being caused by ATC, but that isn’t always the case, and as you may have guessed at this point, I have a story.

A little background:  I got a call from a man in the process of buying a Pilatus PC-12.  Good deal – it was a 2001 model, Series 10, which had spent the past 11 years with a single corporate owner, professionally flown, and maintained according to factory recommendations, just completed an Annual Inspection, all of which had been verified by a very experienced broker.  The gentlemen wanted me to help him fly it from Hanscom Field (just outside Boston) back to California (since he hadn’t been to Pilatus school yet, a condition of his coverage).  Of course I could do that, so we laid out our plans.  Since he had “taken delivery” of the plane in Denmark and had a US N number already assigned, along with a current, permanent US registration, he had it ferried to Boston, where we’d pick it up and fly it back to California.

My job(s) were to plan the flights from Hanscom to Reno (which meant at least one stop, and with bad weather, perhaps two), from Reno to Phoenix, and from Phoenix to San Jose.  In addition to planning the flights, I would get the owner some practical experience in the plane, and begin training him on the planning process, and the procedures and discipline necessary to fly a plane like that.  Pretty straight-forward stuff, I thought.

Plan A – Arrive at the plane late Sunday after the commercial flight and a rental car ride.  Meet the ferry pilot, and get the keys and documents.  Have a leisurely dinner, spend the night, and fly out early the next morning to stop at Sioux Falls, South Dakota, on to Reno for the night, then on to Phoenix the next morning and back to San Jose.  Clearly a bit more flesh needed to put on those bones, but it was a place to start.

Flying (commercial) out to Boston, we discovered by way of the ferry pilot, that the flaps wouldn’t extend on the Goose Bay – Bangor leg, so the ferry pilot brought it into Hanscom without flaps.  Not good, and not the way either the new owner or I wanted to fly the plane.   And, oh by the way, the GPS database was the current Atlantic DB, great for flying to Iceland, Greenland, and Goose Bay.  But if we wanted to fly anywhere in the US we needed a US database.

Plan B – Fly to Manchester, NH Monday morning, where there is a Pilatus service center to get the flaps fixed and get the US database installed.  But to get there IFR, we needed to use a combination of raw data (VORs) and user-defined waypoints to do the departure procedure and to fly direct to the en route and approach waypoints.  And that probably meant we wouldn’t spend Monday night in Reno.

By the time the flap and database issues were sorted out and we got the plane refueled, it was already 1600 local, which would put us into Reno somewhere after midnight.  Recognizing that as a dumb idea, we came to:

Plan C – Fly to Pierre, SD for the night.  With full fuel, we can go that far and still have a 500 pound reserve (which is about as low as I like to take a PC-12).  The forecast showed we wouldn’t need to put the plane into a hangar, as there wouldn’t be any icing overnight, allowing an early start without the cost of a hangar.

The en route winds were stronger than forecast at flight level 240, which I’d planned as a nice compromise between flight time and fuel burn.  That made it a bit iffy about arriving with a fuel reserve that would make me feel warm and fuzzy.  Especially if ATC chased us around as they often do.

Plan D – Ask for and get FL280.  Climb as rapidly as possible, and then maintain the altitude as long as possible before descending.  Even though the winds were stronger at altitude, and even though we could have made it into Pierre as much as 20 minutes earlier by flying lower, this way we landed with the “required” reserve, taxiing in with 36 pounds more than my personal minimum. 

After an early morning preflight, we started the engine and even before pulling out of the parking space, the Environmental Control System (ECS – a fancy way of saying the heating and pressurization system) turned off without anyone touching it.  It died repeatedly during the taxi and we took off un-pressurized.

Plan E – Our maximum altitude is now 12,000, which is too low for the MEAs (Minimum En route Altitudes) required for instrument flight, and it’s really IFR out there.  Fortunately, we have oxygen aboard so we could (for limited times) romp up to altitudes in the 20,000 range or higher as required.  But it meant landing with less fuel than I’d planned, but still above the required 500 pounds.  And it meant refilling the Oxygen tanks in Reno.

After picking up our passengers in Reno and heading to Phoenix, everything worked exactly as planned.  However, between Phoenix and San Jose while at Flight Level 260, the ECS quit again, not to restart. 

Plan F – Call ATC, explain that we have a pressurization problem and ask for 14,000 immediately and 12,000 as a final.  ATC asked if we were declaring an emergency.  The cabin was bleeding down slowly, not an explosive depressurization, so we had time to get below 14,000 feet before the cabin altitude climbed to over 14,000.  Fortunately, all the MEAs from there into San Jose were below 12,000, so we had no problems with oxygen.

Plans A through F were just the ones that changed due to circumstances and our reactions to them.  Of course, there were any number of other routing changes initiated by ATC.

The bottom line is that some changes occur in time to update your plans before the flight; some cause you to make changes during the flight.

Fortunately, most flights require fewer plan changes and smaller ones than this one.  Still, it was a great flight.

Comments