There's a few things I think I can clear up here. I work with power conversion everyday, being an Electrical Engineer specializing in power design. (I hate to sound so WOW is me but I wanted to qualify).

Anyhow here goes:

• Inverter / Converter - Are used interchangeably in the industry. They both mean that Voltage is changed in some form or another. Typically it is either going from 120Vac-->19/12/6...etc Vdc or vice versa.
• Adapter - These are usually devices that take usually change the Mechanical interface but not the voltage. Think of it as changing a square shaped hose to fit onto a round hole (not the best example but you get the idea). *Note: just to confuse you even more, some companies use the term adapter to mean a converter as well. ie, Your cordless home phone, computer speakers, printers, etc - all come with Converters that manufacturers refer to as Adapters.

Okay, anyone still with me? Now, as far as which device to use on a plane (AA)? I would have to recommend This one from iGO. It will work on the plane, in the car and at home / hotel. With this one would only have to bring this device with them. This outputs 70 Watts continuous power which should be enough for most newer laptops as the typical consumption is 65Watts. Of course they call it an adapter though... I use it with my laptop and works great.

BTW, if you laptop doesn't say how many Watts on the Converter it's simple to calculate. Multiply the Volts x Current (Amps) = Watts.

ie, Output of 19V @ 3A = 57Watts.