Originally Posted by
atman
The Brompton only fits with the saddle turned as shown in the picture I've attached. There is very little room for error on either side. The photo is meant to show you how the bike looks as it disappears into the machine, wheels first.
To be perfectly clear, with the saddle pointing forward in the usual way, the Brompton will not fit through the screening machine. You must tilt the saddle to the side as shown; another option is removing it entirely and chucking it into the T-bag, but I don't bother. I must be the only person who feels this way, but it's just a saddle; it's got scuff marks already and it's going to get more.
So that's your bounding box. If you can find any dimension of the Curve which will fit in that envelope, you're good to go.
atman, sorry for getting back to this, but I am looking ahead to taking the carry-on plunge. Measuring the outline of my Brompton, I am getting the same width of 23 inches whether I turn the saddle by 90 deg, and consider the Brompton moving forward with its wheels down the conveyor belt, or whether I consider the Brompton moving forward with the saddle or with the joints, i.e. 90 deg turned orientation to the first. After the saddle is turned, the bike outline becomes square-like, 23" x 23". However, if I were to put the bike forward with the joints, I would actually not need to turn the saddle away from its natural orientation, keeping the outline at something like 24" x 23". Is there any particular reason you used the wheels forward, or have you just not tried the other, 90 deg turned, orientation?