Newcomers to this page: there is a crazy company I’ve been writing about for 14 years, which seems to be a little less crazy than it once did, and when there’s a new development — having over the years bought an insane number of shares — I am like a dog who hears the dull thud of the spoon against the dinner pail.  I drop everything (I had planned to write about the Affordable Care Act today) and run back to the house.

And so, dear fellow shareholders, skeptics, and air travelers everywhere  . . .

There’s a story in the current Aerospace America (“Runway Taxiing Goes Green”) that’s not linkable but says (emphasis added):

What could be one of aviation’s biggest environmental advances in 30 years now appears to be a matter of “when” rather than “if.” Two companies report they are closing in on electric technologies that would let planes taxi between airport terminals and runway holding areas without using their engines.

One of these firms is a small startup called WheelTug; the other, known as EGTS, is a collaboration by three manufacturing giants. The two companies are pursuing very different technical and business strategies, and WheelTug reckons that its technology could be ready to enter service within two years.

. . . [there would be fuel savings] [though the writer reports that WheelTug operates off batteries, when in fact it draws power from the plane’s “auxiliary power a unit,” which itself runs on jet fuel] . . .

Turnaround times between flights also would be reduced. Planes would not have to wait for tugs, or to be coupled to them and then uncoupled. Moreover, a plane’s wheel-mounted electric motors would allow it to turn sideways safely in congested ramp areas without causing any jet-blast damage.

This ability—a concept WheelTug has trademarked as the “Twist”— could produce the greatest cost saving of all, says Cox. It could allow planes to disembark and board passengers at two adjacent gates simultaneously, slashing turnaround times by a third.

This could create enough extra utilization time in the day for a shorthaul aircraft to operate an additional, revenue-producing sector. Taxiing on battery power generated by the auxiliary power unit would also be much quieter than taxiing even on one engine. Aiming at single-aisle

. . .

Although WheelTug doesn’t offer system redundancy, it’s much simpler and lighter than the EGTS system, which might make it easier to earn airworthiness certifications from the FAA or other authorities around the world. WheelTug uses a nose-landing-gearmounted electric motor to drive the nosewheel, to taxi and to turn the aircraft. One criticism, from some aircraft analysts and from competitor EGTS, is that its nosewheel location sometimes makes it unable to provide enough traction to push back or taxi a plane when the weather is snowy or icy.

Cox’s answer to this is that WheelTug’s business model is not to sell the system to airlines, but merely to charge them service fees representing a fraction of the actual savings that customers realize operationally from using it. Only WheelTug would be out of money if bad weather didn’t permit its use. To date, WheelTug has garnered commitments from 13 airlines to fit 731 single-aisle planes, mostly Boeing 737s. One, Icelandair, intends to use the system on its future Boeing 737 Max jets, but this is a separate certification challenge, because the noselanding gear of tomorrow’s 737 Max is different from that of today’s 737NGs.

As a small company, WheelTug’s biggest headache could be that Airbus and Boeing do not sell the design-engineering data for their aircraft cheaply, if at all. This makes it extremely difficult for third parties to perform a full FAA—or equivalent— certification process for aircraft major structural modifications. Instead they usually seek a simpler certification method involving issuance of a supplemental type certificate, which is applicable only to minor structural modifications.

This has been a thorny problem for WheelTug. Cox says the planned late-2014 certification date has slipped to “well into 2015,” and that WheelTug has recently simplified its system significantly, mainly to lighten it. WheelTug has done so partly in the hope it can obtain a supplemental type certificate for the system and so avoid the need to buy manufacturers’ engineering data for certification. The system is now called V1 and is operated by a pilot rather than ground staff as originally planned. V1’s maximum taxi speed is lower than that of the original version.

Cox says the company might still need to buy manufacturer engineering data to achieve certification. But while WheelTug has not yet chosen the aircraft type on which it will first certify the system—the choice depends on having a customer aircraft available for long enough to do so—it has chosen to certify V1 through the FAA rather than through EASA, the European Aviation Safety Agencies.

This is because “EASA relies on Airbus,” Cox says. Since Airbus is now allied to EGTS and the A320 family is under the airworthiness oversight of EASA, it appears likely WheelTug will look to certificate V1 first on a Boeing 737. Once the system receives certification for one aircraft type, getting it for other types should be relatively simple.

The technical and certification challenges for EGTS will be harsher than those for WheelTug, according to Paul Brooker, chief technical manager of IBA Group, a U.K.-based aviation technical services firm. Designed for the A320 family and already demonstrated experimentally, EGTS is a dual system that uses an electric motor mounted on a wheel on each main landing gear unit. Though it offers system redundancy, EGTS is much heavier than V1 and requires air cooling. In addition, its motors are located close to each main landing gear unit’s brakes.

EGTS will operate in “an extremely hostile environment,” says Brooker. Its motors will be exposed to potential hydraulic leaks, to sizable landing stresses, and—because of the system’s proximity to the plane’s carbon brakes—to extremely high temperatures and to brake dust. Brooker thinks EGTS may be more likely than WheelTug to experience technical problems in routine operation, particularly after several months in service.

That said, the size, technological expertise and market clout of the EGTS partners should help get their system through EASA certification— this will probably happen later than WheelTug’s certification—and into sales contention. The EGTS partners are “already flooding the market” with their sales efforts, says Brooker. He reckons both systems have considerable market potential and should be particularly attractive to airlines serving remote, ill-equipped airports.

And here’s another story, just out, that suggests the state of play on WheelTug.

I’m sorry to insert the whole thing — it’s not on-line and I haven’t learned how to link to a .pdf.

The bad news — which of course we’ve known — is that Boeing and Airbus are still not on board.  (Also, that Honeywell/Safran say that their system will not impede brake cooling.)

The good news is that, as one reads articles like the ones above and below, e-taxi seems inevitable.

Also, our system appears to be several hundred pounds lighter than theirs; ours can be installed (and uninstalled) in a day and requires zero financial commitment from the airlines; we’ve signed 14 airlines to their zero; and we have patents up the wazoo, which might even matter someday.  (Ever hear of Elisha Gray?  No?  Well, that’s the point.)

The title of the article — “WheelTug Is Not For Turning” — is a bit odd when you consider that a key feature of the system is its ability to turn the plane parallel to the gate, instead of nose in, for boarding and deplaning from both front and rear simultaneously.  The phrase plays off one of Margaret Thatcher’s most famous pronouncements — “the lady’s not for turning” — as she stayed the course of her painful economic plan (that arguably led to the rescue of the British economy).  I.e. (I guess): WheelTug plows ahead, undaunted.


Have a great day.


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