Forever Stuck at Mach 0.70?
If ever there were click bait for naysayers, it would be this week’s announcement by Boeing that it’s exploring a Mach 5 passenger jet capable of hopping the Atlantic Ocean in two hours and the Pacific in three. Boeing revealed the concept at the American Institute of Aeronautics and Astronautics.
As a more or less professional naysayer, I naturally clicked on the link. Aviation Week had an excellent technical summary of the Boeing concept, which is nested in a group of emerging technologies driven as much by the military market as by civilian demand. For years, Boeing has been dabbling in hypersonics and even the new Mach 5 concept vehicle relies on research extending back to the company’s aborted 2707 SST cancelled in 1971.
As you would naturally expect, Boeing’s hypersonic group concedes the technical challenge while at the same time suggesting the developable technologies are there to solve these. They’ll need to figure out cooling for the airframe and cabin, weight and fuel considerations and, above all, combined Brayton cycle turbojets and ramjets that cocoon the engines' conventional rotating machinery. The airplane would accelerate to some low Mach number on the turbojet and the ramjet section would take over to establish Mach 5 cruise. Exotic stuff.
My naysayer radar illuminated a sticky point in this concept and it’s not technical, but economic. The Boeing hypersonic group likes Mach 5 because it allows a traveler same-day return on a business trip. Boeing says this gives the would-be HyperLiner airline better use of assets, too. And they’re gonna need all they can get.
But let’s break this down. If I have a business meeting in, say, Tokyo, that’s so important that it’s worth—$40,000 in airfare, maybe?—what’s my day gonna be like? Let’s say my meeting is at 10 a.m. Tokyo time. Los Angeles is 16 hours behind Tokyo, so allowing for airport travel and the three-hour flight, I’ll need to leave at 1 p.m. LA time, arriving in Tokyo at 6 p.m. California time. (It’s now 10 a.m. in Tokyo.)
Not too bad. Maybe a cup of coffee will get me through it. Meeting done, I board the afternoon flight back to Los Angles, where it is now 1 a.m. the same day I left. Four hours later, I’m home at 5 a.m. This flight is not really a red-eye because it’s not long enough to get much useful sleep.
Let’s go the other way, New York to London. For my 10 a.m. meeting, I’ll need to leave for JFK at 1 a.m. local time. After the meeting, the afternoon flight gets me home mid- to late afternoon, in time for dinner. An awfully long day, but maybe tolerable.
So Boeing’s bet is on finding enough people with enough money who are willing to put up with such killing schedules for the sake of … I’m not sure what. Are there sufficient people in the world whose time is so precious to constitute a market profitable enough to entice an airline to invest several hundred million bucks to make it happen? I have little doubt that the world wealth is there to do this. As I write this, I’m sure several dozen jets are flying wealthy clients across the Atlantic and Pacific in cracked-lobster splendor. But are there enough to fund a fleet of hypersonics? Now or in the late 2030s when Boeing might deliver such a thing?
On the other hand, I like to imagine that my naysaying is leavened by a more expansive grasp of history. The history of transportation, from feet stuffed into dusty sandals, to carts pulled by beasts of burden, to trains and automobiles has always been, directionally, about increasing speed.
In mass aviation transportation, we have been stuck at Mach 0.75 or so since the 1960s and, except for the Concorde’s brief flame, have actually regressed since the Boeing 707 smoked along at 607 MPH. Taking the longer view, a hundred years from now, will we still be stuck at that speed, continuing to trade improving economy and efficiency for the same old plodding cruise speed? My bet is no.
The formula has worked, after all. The Miami-Barcelona round trip ticket I bought earlier this month cost $825. In inflation-adjusted dollars, that’s $75 less than I paid for a similar trip in 1971—47 years ago. Perhaps not miraculous, but remarkable nonetheless. While I’d be delighted to make the trip in two hours or less, I’m sure I’ll never be able to afford that. But I derive no small satisfaction in believing that one day, someone will.