Q. Recently I flew on Hawaiian Airlines from San Diego to Honolulu and and they brought out a portable luggage scale at the gate to weigh our carry on bags. Any bag over 25 pounds had to be checked in at the gate and a checked bag fee had to be paid. You couldn't get on the flight without a sticker showing the bag had been weighed. Is this a common practice?

A. I have to be honest, this is the first I've heard of this, but checking Hawaiian's website there is indeed a 25-pound limit on carry on bags (11.5 kg). Checking further, I see that a number of airlines, mostly foreign-based ones, also have limits, some as low as 15 pounds (EVA Airways for example). I tweeted an inquiry from @airfarewatchdog and learned from followers that many travelers have been surprised by these limits, including those flying on Lufthansa, British Airways and Ryanair. Even worse than paying a checked bag fee, when a carry on bag is snatched from your hands at the gate upon boarding you might forget to remove medicines, valuables and electronics from the bag. Airlines do not take responsibility for these items if they're lost in transit.