In this month’s Flight Training Magazine (1/2011) there’s an easily overlooked tip that I think many people would find helpful. When teaching new pilots (or even working with some experienced ones) I often find that there is some confusion in knowing how to plan a descent. This results often in arriving high into the airport area and having to dive into the pattern –which we don’t want to do!
So what’s a good way to plan your descent?
Use the “Rule of Three”!
To do this, multiply the number of feet you have to lose by three.
If you are cruising at 6,500 feet and you have to descend to a traffic pattern that is 1,500 feet, you need to lose 5,000 feet. Now multiply 5 x 3 and you get 15…start your descent 15 miles out.
Now what should be your rate of descent?
The folks at Flight Training Magazine recommend taking half your groundspeed and multiplying by 10. So if you are cruising along at 120 knots GS, divide by 2 (=60) and multiply by 10 which gives you 600 feet per minute.
A little number crunching can make for a much more comfortable and pleasant ride into an airport traffic pattern!