Nice wheel. Well, it was once anyway.

Road Tubeless is great.
It’s that simple. The tubeless setup I previously detailed ran straight and true for several weeks. It was fast, grippy and light.

Then the crash happened.

Briefly

I was on a very fast steep descent on a wet day with a gale howling and entering a corner. What could possibly go wrong?

Going along at 55kph I went through the first corner of the descent from Sallygap towards Rathfarnham. The wind which had been behind me was now coming from the side, and a stronger gust surprised me. Totally side-on now it pushed me, fully sideways across the road. With no other traffic around I was able to attempt all the proper corrections in safe haste – counter steering, steering into corner, braking without locking up. I threw the literal rulebook at the bike.

Nothing worked and I hit the lip of the ditch sideways on. The rear wheel dug in while the momentum carried the bike on and flipped me bodily over the ditch.

Dried up sealant filling gaps around spoke hole.

The Result

All of the equipment was fine bar one scratch on the chainstay and a catastrophically failed rear wheel. As can be seen from the photos the wheel is completely warped beyond repair.

The rim seam burst and the air-tight seals around the spoke holes burst open. But there it stopped. Sitting there in a ditch I watched the Stan’s No-Tubes sealant bubble forth through the split in the rim and the spoke holes. At first I wondered what the hell it was, then remembering, I watched as it stopped bubbling 20 seconds later. That was it. Sealed.

Burst seam on the rim, now sealed.

The accident was four weeks before these photos were taken. The tires have remained sufficiently pumped up to be used (although the wheels’ buckled state might have a say in that).

Please Note

Throughout this post the pneumatic buffers which run between a bicycle’s wheels and the road surface have been referred to as “tires”. If you prefer “tyres” then good for you, you are staying true to the roots of the English language. But language moves on, so get with the programme, and stuff.

Original content created by: The Inquisition

The Albatross mid-test-flight at Drysden Air Centre

The Gossamer Albatross might well be the coolest bicycle ever. Aside from having a name that could be confused with being an exclusive, designer condom, this bike was a plane. Pedalled by Bryan Allen in 1979, it flew 23 miles across the English Channel to Boulogne. Thirty years later, it is still an amazing feat.

It wasn’t the first human powered flight. That honour went to Gabriel Poulin, in 1921, when he won 10,000-franc Prix Peugeot, the first prize for human powered flight at Longchamps racecourse. Another notable mention here would be MIT’s Daedalus which came very close to flying from Crete to Santorini in 1988. Much like its Grecian namesake it met a watery demise.

The cold, hard facts: 34ft long and 16ft high, it had a wingspan of 98ft. The wing area was 488ft². Its empty weight was 70lbs, and its maximum measured speed was 18mph. But who cares? Its a flying bicycle.

The Albatross was created by Dr Paul MacCready, whose company, AeroVironment, is the market leader in researching clean energy solutions for sustainable flight and transportation. Mc Cready went on to produce a solar powered variant, the Penguin, which flew from Paris to the UK in 1981. These days MacCready may be best known for his unmanned solar aircraft produced for Nasa – the Pathfinder series. These have raised the possibility of infinite flight as their batteries can retain sufficient charge to fly through the night.

Nasa's solar-powered Pathfinder series, developed by MacCready.

Variants 1: Human-powered Helicopters

These must be one of the singularly most unimpressive areas of human endeavour. The physics are just too unfeasible to make such flight worth it. As with all boffin-baited challenges, this does not stop people trying.

Although the Sikorsky Prize has not yet been awarded the California Polytechnic State University Da Vinci III, flew for 7.1 seconds and reached a height of 20 cm in 1989. The prize will be awarded to the first entry to reach an altitude of 3 meters (10 feet) during a flight lasting at least 60 seconds, while remaining in an area 10 meters square (36 feet square); so you can see it is completely pointless.

MIT's Daedalus Humna-powered aircraft

Variants 2; Others

There are, or have been a bunch of others:

• Poulin’s Avietta
• AERSP 404H
• Bossi-Bonomi Pedaliante
• DUT Icarus 001
• Gossamer Condor (The Albatross’ Precursor)
• MIT Daedalus
• PSU Zephyrus

Bonus Material

Paul MacCready talks at TED

Bibliography
Fiddlers Green – lightweight aviation enthusiasts
AeroVironment
AeroVironment NASA page on the Albatross
NASA page on Daedalus
Royal Aeronautic Society

Original content created by: The Inquisition

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