This is your pilot speaking. Thank you for flying CWA – Collected Wisdom Airlines. We're coming in to land at … Just a minute, I have to let go of the controls to take this text message …
The question
Why, asks Eric Morris of Montreal, are you not allowed to use electronic devices when a plane is taking off or landing, but you are allowed to use them when the aircraft is at cruising altitude?
The answer
You can actually use them before the plane gets to cruising altitude (25,000 to 35,000 feet) as their operation is often allowed once the aircraft is above 10,000 feet and the seatbelt light goes off, writes Dave Gamblin, a licensed pilot living in Fredericton.
"Below 10,000 feet, the navigation of the aircraft is critical," he says, "as the plane is at low altitude, in close proximity to many other aircraft, and in a dense traffic area. A minor error in navigation caused by interference to the plane's equipment by an unauthorized electronic device could easily be catastrophic."
Also, during this "high-risk" period in the flight, he says, it's not a good idea to have your hearing impaired by headphones when you might need to react to emergency instructions.
Once the plane is out of this statistically more dangerous part of the flight, Gamblin writes, passengers are allowed to use electronic devices.
However, Russell Ong of Vancouver says there is no definitive evidence that electronic devices interfere with airplane instruments or controls. "It is only as a precaution that airlines do not allow electronic devices during takeoff and landing, but even this policy is under review."
The question
David McCray of Walkerton, Ont., was watching a documentary about the Second World War and noticed that German U-boat skippers wore their peaked caps backward while peering through the periscope to stop the peaks from getting in the way. Why wear a cap in a U-boat at all?
The answer
"While I can't speak to German naval customs, one of the rules in force during my time in the Canadian navy in the 1980s was that the officer in charge on the bridge while the ship was under way had to wear some type of headdress (military jargon for a cap or hat)," writes Jon Lasiuk of Toronto. "This made him (or her, these days) instantly recognizable as the officer of the watch" – the person in command. Except for ceremonial occasions or when coming alongside a dock or jetty, "ship's company were not usually required to wear caps while on board – a pleasant change from the otherwise stuffy uniform regulations of that era."
The question
What is the best colour to wear to show off a tan? Jackie Phillips of Toronto wants to know.
The answer
Henry Ko of Dorval, Que., says that in Chinese culture, a tan is bad, as it shows you work outside rather than in a cushy office job. "My mother told me not to wear yellow as it accentuates your tan. So if you believe my mother, wear yellow."
Help wanted
How do spiders connect their webs between trees? asks Don Holmes of Duncan, B.C.
Why does the Royal Canadian Mint put dates on our money? Paul Eastman of Victoria wants to know.
Robert Findlay of Toronto writes: "How did the Republicans choose an elephant as their party symbol and the Democrats a donkey?"
Let's hear from you: If you have the answer to one of these questions (or a question of your own) send an e-mail to wisdom@globeandmail.com. Please include your location and a daytime phone number.