That is because, unlike the rockets currently used to get into orbit, they are air-breathing.
Currently, the fastest air-breathing aircraft is the SR-71, which accelerates to slightly over Mach 3.
Its disruptive technology is a novel air-breathing and rocket engine that would enable the ship to go to space in one leap.
Route 66 boasted a full luxury interior with air-conditioning, desalination equipment and even an air compressor for underwater breathing hoses.
The boat, called Route 66, cruised at more than 20 knots and frequently hit speeds in excess of 30 knots, or 55 kilometers an hour. (Note that America's Cup racers max out at 16 knots, and they're basically empty shells with nary a cushion to sit on.) Route 66 boasted a full luxury interior with air-conditioning, desalination equipment and even an air compressor for underwater breathing hoses.
They stroll along Ojai Avenue from art gallery to art gallery, enjoying stunning views of the Topa Topa Mountains and breathing in the smog-free air.
Prop traders, even if they are "ring fenced" from other trading desks, still have access to information the bank has on customer positions, if only by virtue of breathing the same air as their client-facing colleagues.
Breathing particulate-laden (aka smoggy) air may be hardening your arteries faster than normal, according to research published today in PLOS Medicine.
To cope with air pollution in China, artist Matt Hope produced a "Breathing Bike, " that consists of a fighter pilot's breathing mask attached to a pedal-powered air filtration system.
And while a rejuvenated Bristol are breathing the rarefied air of the Premiership, Evans could be rattling round a half-empty Stoop, a fallen squire cursing the cruel realities of the modern game.
BBC: SPORT | Rugby Union | Quins must focus on business of rugby
Desperate for fresh air, he tore down churches and apartment blocks in a now-lauded attempt to give the city breathing room.
When we put in place new common-sense rules to reduce air pollution, like we did in December, it was to prevent our kids from breathing in dangerous chemicals.
WHITEHOUSE: President Obama Speaks at Conference on Conservation
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