[M]any of the 4m Britons who travel to the United States each year will no doubt be delighted to hear of a plan to station American immigration officers at two British airports, London Heathrow and Manchester. These will process travellers before they leave the country, and with luck considerably speed up entrance at the other end. And, as the Telegraph goes on, processing people before they board the plane would be popular on both sides of the pond....
Pre-arrival clearance has been available for those flying from, or refuelling at, Shannon airport in Ireland for some time. This was one of the bonuses benefits of IAG, the parent of British Airways, acquiring Aer Lingus, an Irish carrier. Eight other European airports may also be included in the scheme, reports the Telegraph, including Schiphol in Amsterdam, Madrid-Barajas and Arlanda Airport in Stockholm. Still, it will probably take two years for officials on both sides of the Atlantic to agree upon and then implement the scheme in Britain. And, of course, there is always the danger that the immigration officers that are sent over here will be just as surly and incompetent as those they employ at home. But let’s stay optimistic.
The other benefit to pre-clearance is that travelers will be able to connect directly to domestic flights in the U.S. Right now, people going from London to, say, Des Moines, have to land at O'Hare, go through customs and immigration in Terminal 5, and then re-check their bags and go through security in whatever domestic terminal they're leaving from. This makes the minimum sane connection time about two hours. With pre-clearance, passengers can get off their plane and walk a few gates over to their connecting flight.
For me, though, it'll probably only save about fifteen minutes, thanks to Global Entry. (If you travel outside the U.S. more than once a year, definitely apply for this program.)
It's not clear when this will actually happen. There are challenges. The Department of Homeland Security has not yet announced a date for implementation.