Ask Captain Lim

Dear Captain Lim,

I'm yet another aircraft lover and an aspiring pilot with many question in mind to ask you. I have read through almost your entire website and it really boost my knowledge about airplane and about being a pilot. I wish to thank you for setting up this fantastic website as well as to ask you a couple of questions.

One thing I notice about the difference of a cockpit of Boeing 747-400 and Airbus 320 is the control wheel. In an Airbus 320, the control wheel is located to the side of the pilot while the control wheel in a Boeing 747-400 is right in front of the pilot. Why is the control wheel so different in a Airbus 320? Isn't it more convenient to have the control wheel right in front of the pilot? What is the advantage of locating the control wheel to the side of the pilot?

What would happen to a passenger aircraft when a pilot extends the flaps or the slats of the aircraft in the middle of a flight by mistake?

During my trip from Singapore en route to Hong Kong, I noticed that the when the Aircraft (an A320) landed, the landing was quite bumpy than usual as the aircraft vibrates strongly while decelerating on the runway. When I got off the plane, I observed that the pilot moved briskly under the plane towards the main wheel even before all the passengers have disembark. As he approached the midsection, he looked up and examine the plane under part.

What could have been the problem? (surely it isn't a flat tire!)

Thank you,

Regards,

Sammy Peh

Hi Sammy,

By locating the control wheel onto the side of the pilot, Airbus has revolutionized the way a pilot manipulate the flight controls in the new cockpit. They call them the side sticks - they are basically the norm in the modern fighter plane cockpit. When installed in commercial airliners (Airbus A330/340/380), they provide more space to the pilots. In fact, the pilots now have a so-called desk each to place all their manuals, food, etc.

On the Boeing 777, as a safety feature, it is not possible to select the flaps or slats above 265 knots at 20,000 feet or above. On most planes, there is a flap gate to prevent the inadvertent selection of the flaps or slats during the cruise. What would happen if it were selected by mistake? Well, the plane would pitch up and climb and damage on the flaps is likely.

Yes, severe vibration after landing may be a sign of tire failure.