Pardon me, I know these are very old comments.
Not necessarily, and those ~1mm tall lap joints may instead provide some usable vortices.
Or they're deep enough in the boundary layer that they don't really cause significant drag. (I haven't done any studies at that level to know)
The loss of strength is calculated for, and I'm not sure that FSW is viable with high end aviation alloys like 6061 or 7075. Both of which are hardened before final shaping and drilling. I don't like curving and cutting in T6 if I can avoid it, but I don't want to risk the welds cracking due to overhardening, either.
Here's where
I think you're misunderstanding why the 747 and A380 are coming out of favor except with very few users.
Mentour Pilot on YT has a thing about the 747 and A380.
View: https://www.youtube.com/watch?v=TaKNmbLDS_w
Both 747 and A380 were designed around an assumption of hub-and-spokes airline operations. Different times for each, yes, but both designed around the assumption that short ranged planes would deliver passengers to a relatively small number of hub airports that would then dispatch long ranged planes to other hubs, then the passengers would transfer onto another short ranged plane to go to their final destination. Say, Denver to New York to Paris to Rome, changing planes every time.
But people really learned to
hate changing planes. It never fails that you have to run to the terminal at the other end of the airport at Atlanta, for example (that's about 2 miles away), because your plane is half an hour late and you only have a 1hr layover...
So airlines learned that if they could get a plane with enough range to fly direct,
they'd fill that plane. So carriers like Southwest would deliberately avoid most of the major hubs and then go to the smaller airports around them. So, direct from Boise to San Jose/Palo Alto, instead of Boise to Salt Lake City to San Francisco (and drive to Palo Alto). Or Denver to Rome direct, for the international version.
The other issue is that
the 747 and A380 are only cost effective when they're operating full. If you cannot fill the plane reliably between those hubs, you're not going to make money on it.
Now, Emirates
is making it work, generally, using Dubai as their major hub. But they're also in a pretty unique geographical position, able to keep the A380s pretty full when flying from Australia to Dubai or Asia to Dubai. Helps when they're also carrying people for the Hajj.
Or at least write up blueprints and then have someone else make something from them.
Because I have a BBA and had to pass calculus and statistics in order to get it.
It's Seattle. It rains something like 330 days out of the year there. The joke is that the rain festival is from January 1 through December 31.
737-800
737-900ER
