Originally Posted by
emma69
However, I believe (and perhaps someone can confirm), that the arm rests on these aircraft are fixed in First, meaning you would have a max of 21 inches. If you bought 3 economy seats between the two of you, you would have 3 x 18 inch seats, and you would be able to lift the arm rest. So pick the option you think would be most comfortable for you.
Yes, I am fairly certain the middle armrests in First Class on the A320 series are immovable because they contain the tray-table. The aisle armerests on the newer AA aircraft may be movable, but the airline usually requires them to be lowered for takeoff and landing.