Ask the Captain: How far does a jet fly during its lifetime?
Question: How many miles does an airplane like a 777 fly over the course of its lifetime?
-- submitted by Bryan Corbin, Doha, Qatar
Answer: A challenging question! If you use the following assumptions:
- A 30-year lifetime
- 3,500 hours a year as an average
- An average speed of 500 miles per hour
- 30 x 3500 x 500 = 52,500,000 miles
That is approximately 2,080 circumnavigations of the Earth, 109 round trips to the moon, or the average distance to Mars.
Q: How fast does a 737 climb to cruising altitude?
-- submitted via e-mail
A: The airspeed maintained in the climb and the rate of climb depends on the weight of the 737 and the outside air temperature. So the direct answer to your question is "it depends."
What is the weight, temperature, the cruising altitude to be flown? The answers to those questions determine the answer.
A rule of thumb for 737 pilots is 250 knots to 10,000 feet, then 280 knots until reaching Mach .74.
Q: Regarding last week's column, was the 707 looped by the test pilot?
-- submitted via e-mail
A: To my knowledge, the Dash 80 (the predecessor to the 707), was only rolled not looped. I do not know of a case of a commercial transport jet being looped.
John Cox is a retired airline captain with U.S. Airways and runs his own aviation safety consulting company, Safety Operating Systems.