Anything you can do …
Oh boy!! If you like bizjets, nothing beats a couple OEM marketing departments feverishly chasing esoteric distance records around the world at top-speed with their brand new $70M jets. It’s like the aeronautical version of Nathan’s Hot Dog Eating Contest.
But big corporations rarely go full-tilt Coney Island in broad daylight, so when Bombardier and Gulfstream take to preening like a couple heavyweight fighters at a weigh-in, we can hardly contain ourselves.
To catch you up, Gulfstream’s G650ER has been unchallenged as the longest of the longest-range. They say it flies 7,500 nautical miles (NM). But, Bombardier has now certified the Global 7500. And they say it flies 7,700NM. That’s another … 2.6%. Which is no big deal in the real world, but those 200NM are critical for bragging rights.
However – the Global 7500 is brand new, and that means the range numbers are sort of considered unproven by the (always suspicious) marketplace. So, Bombardier wanted to begin establishing the bona fides.
Last month, the Global 7500 flew 8,152NM from Singapore to Tucson and established a new distance record for a business jet. Also established was the somewhat less impressive record for “most effort ever directed at getting to Tucson, Arizona.”
Bombardier’s press release was (not atypical for an OEM) sparse on detail and a little opaque in certain areas. They didn’t directly state the flight time; instead listing just the departure and arrival time. Maybe that was stylistic, or maybe it was intentional. Either way, if you had an extra 45 minutes to spend researching time zones, you would have found the flight took 16 hours and 6 minutes or so. Without the benefit of knowing the wind component, which they also didn’t state in the press release, this flight time appeared a little on the slow side for an aircraft that is supposed to cruise at .85 Mach.
In the end, without more data, it’s difficult to know how impressive this flight really was, or how much it truly revealed about the aircraft’s actual performance compared with its advertised performance.
Also interesting: the fun interactive map on Bombardier’s own website seems to indicate that the Global 7500 won’t make Tucson from Singapore:
For reference, here is the set of assumptions that Bombardier lists in the footnotes for this chart:
∆Performance on this page is based on the following assumptions: ISA+15ºC takeoff temperature, 8 passengers, 4 crew (225 lb. each), M 0.85 cruise speed, 3% airways allowance, ISA conditions en route, 85% Boeing annual winds, NBAA IFR (200 NM) fuel reserve, standard configuration BOW.
These are important. Back to these in a minute.
Meanwhile, with pride in the balance, Gulfstream was presumably hard at work in the G650ER performance books. They’ve previously publicized some other G650ER flights: Singapore to Las Vegas, 8,010NM in 14+32; Singapore to San Francisco, 7,475NM in 13+37 at .87 Mach; Los Angeles to Melbourne in 14+58. All really far but, now, just second best.
Here’s where things get dramatic … Last week Gulfstream sent the G650ER to Singapore in an attempt to re-break the record. They claim to have landed in Tucson (how ironic!) 15 hours 23 minutes later, beating the Global 7500 by 44 minutes while flying 225NM farther (we assume this is to do with the flight routing and not because Tucson has been relocated).
For the record, Gulfstream’s press release was not exactly rife with detail either, apart from the distance and flight time.
Here is what Gulfstream’s fun interactive range chart shows for the G650ER departing Singapore:
* NBAA IFR theoretical range. Actual range will be affected by ATC routing, operating speed, weather, outfitting options and other factors.
** G280 ranges shown with 4 passengers, G650ER, G650, G600, G500, and G550 ranges with 8 passengers.
** G500 and G600 performance is based on preliminary data and subject to change.
These conditions are, at first glance, are a little more generous than the ones Bombardier claim to have used in their chart – or at least less descriptive. We don’t know and therefore can’t directly compare the charts against each other – and we also really can’t correlate these charts against the two record setting flights in question. We can’t even conclusively compare the two Singapore to Tucson flights against each other. At least not without some more data.
Which leads us to the important thing about range: it depends on a lot of variables. Without clearly understanding all of them, none of these records, press releases or charts should mean much to a consumer – at least at the margin. These are both massively impressive machines, but at the outer limit of any aircraft’s capability is a lot of grey area. For accuracy, the lines on those charts should really be much fuzzier.
The danger of OEM press releases touting specific performance achievements is that most owners don’t understand the nuances. They can set expectations that may be difficult to replicate under different conditions. They can also put pilots in the uncomfortable position of having to explain to the boss why they can’t or won’t do something that the OEM claimed to have done.
We’re not arguing that the OEMs should stop setting records. It’s fun. But here’s a reasonable request: release all of the detailed data pertaining to the flight necessary for an informed consumer, advised by their flight crew or knowledgeable 3rd party, to interpret what really happened. Things like payload, flight-plan, winds, speeds, altitudes, reserves (both planned and actual). Otherwise, these claims of achievement can appear incomplete and highly choreographed.
There is a reason the chapter entitled “world records set westbound” is a short one.