Electric Brakes On Komet Trailer

I am trying to get away from the surge brakes and has anyone converted their trailer to electric brakes?? Thanks

On Saturday, February 16, 2019 at 6:21:22 AM UTC-6, Bob Youngblood wrote:
I am trying to get away from the surge brakes and has anyone converted their trailer to electric brakes?? Thanks

But why change a simple and entirely appropriate device against something complex and in need of fine-tuning (laden vs. empty trailer)? Fix or adjust your surge brakes (Spindelberger website has details) and you'll be fine. Nobody in Europe has electric brakes on glider trailers.

On Saturday, February 16, 2019 at 6:32:07 AM UTC-8, wrote:
On Saturday, February 16, 2019 at 6:21:22 AM UTC-6, Bob Youngblood wrote:
I am trying to get away from the surge brakes and has anyone converted their trailer to electric brakes?? Thanks

But why change a simple and entirely appropriate device against something complex and in need of fine-tuning (laden vs. empty trailer)? Fix or adjust your surge brakes (Spindelberger website has details) and you'll be fine. Nobody in Europe has electric brakes on glider trailers.

The problem with keeping the Komet system is the availability of parts in the U.S. My brake system has been inop since I've owned the trailer and as BobW have found no issues even with heavy braking. I have thought of converting to the more modern axle-less system and electric brakes.

AL-KO brakes simple? Hahahaha! Things that can go wrong include allowing the lining to wear too much without adjusting (brake shoes can jam in full on position), rubber seal going into cable housing can leak (cable rusts and gets stiff inside housing, preventing brakes from releasing), damper strut inside tongue can lose force and/or get stiff over time (preventing brakes from releasing), bushings between inner and outer tongue can swell over time (preventing brakes from releasing), water can leak into tongue and corrode inner tube (see "bushings"), and poorly adjusted parking brake breakaway cable can actuate brakes inadvertantly. And if the front tongue mount breaks and the trailer settles on the tongue, the brake rod is actuated and the brakes are full on. I'm sure there are more, but these are just the things I've seen. I check the bearing cap temp every time I stop just in case. Also frequently after a hard stop, which is how I caught the latest brakes-jammed-on problem this summer coming back from TSA. But I left on the trip with a full set of bearings and seals...just in case.

The surge brake on the Komet/Cobra is anything but simple. And definitely not troublefree. And it requires a fair amount of attention and maintenance. And the failure mode often includes burned bearings or worse.

Europeans drive a lot of Mercedes automobiles, too, but many Americans won't put up with the maintenance costs for the privilege of driving such an exquisitely engineered machine. We just want to get in the car and go. It's a car, not a love affair. I suspect most European pilots don't trailer the miles we do. And more probably store their trailers out of the weather than here. It's a different environment. Today's running gear is better than it was in the days of Eberle and early Komet trailers but it's still not designed and built for our needs.

That said, I've continued to repair and maintain my 27-year-old Cobra. It's a hassle. It requires almost as many inspections as a car, for far few miles each year. And I worry about what could go wrong every time I head out for a contest. But I figure I'd be trading one set of problems for another if I made a change.

Chip Bearden
JB

And remember that most sailplane trailers in Europe are placarded for 80 kph (50 mph) maximum. Unlike the US where 75 mph freeway speeds are the norm.

I should add that I came back from TSA to the East Coast this summer with the brakes disconnected on my Cobra because they jammed full on during a hard stop. I didn't notice much difference pulling it without the brakes with my full-size Chevy van. I've done the same thing in the past for the same reason. It's better than trashing a set of brake shoes, burning out the bearings, and cracking a drum/hub (trust me....).

I think it says something about the engineering approach when it's less trouble to disable a feature even though it's useful. All the assurances that AL-KO brakes work great if they're maintained and adjusted properly aren't much comfort if something goes wrong so frequently that you're tempted to do without.

Indeed, I've thought about just leaving the brakes disconnected permanently.. But I like the parking brake feature. And the braking force does help slow things down in panic stops (even if I do have to climb out and verify the brakes have released afterward).

I'm sure there's a lot more I could learn about maintaining the AL-KO system. But I'm a mechanical engineer with a lot of time doing brake jobs on my vehicles of all sizes and makes. And I worked at Wagner for many years, one of the leading brake parts suppliers in the U.S., where I was very familiar with our products and interacted frequently with our engineers. And I have the manual for my trailer, which I have consulted frequently, and have also searched blogs and discussion groups here and in Europe for insights.

The AL-KO brake system works great when it's new. But I've found it to be fussy and somewhat difficult to maintain as it ages. I'd love to learn what I'm doing wrong but every time I raise a question here that isn't covered in the manual, I get a handful of different answers. And then I discover that a lot of you have had the same problems I have. We shouldn't need a separate forum just to discuss problems with AL-KO brake systems.

Chip Bearden

wrote on 2/18/2019 1:08 PM:
I should add that I came back from TSA to the East Coast this summer with the brakes disconnected on my Cobra because they jammed full on during a hard stop. I didn't notice much difference pulling it without the brakes with my full-size Chevy van. I've done the same thing in the past for the same reason. It's better than trashing a set of brake shoes, burning out the bearings, and cracking a drum/hub (trust me....).
....
Chip Bearden

I tow my 2500lb Cobra with a 13,500 lb motorhome, so trailer braking isn't much
value. I do like the parking brake when manhandling it around on a sloped ramp,
driveway, etc. Is there anyway to easily disable the braking function for towing,
then restore it quickly when it's time to remove the trailer from the hitch?

--
Eric Greenwell - Washington State, USA (change ".netto" to ".us" to email me)
- "A Guide to Self-Launching Sailplane Operation"
https://sites.google.com/site/motorg...ad-the-guide-1
- "Transponders in Sailplanes - Dec 2014a" also ADS-B, PCAS, Flarm

http://soaringsafety.org/prevention/...anes-2014A.pdf

I don't think disabling trailer brakes is a good idea. There is stability under heavy braking to consider not just retardation. I have twice, separated by about 25 years, had the situation of having to emergency brake on a motorway, the trailer start to swing out (not just sway) and then snap straight as the trailer brake bit fully. My impression was that if the trailer had been unbraked one or both times it would have jackknifed and possibly caused a multiple vehicle incident. Thankfully I will never know for sure but I would never tow a glider trailer any distance without good brakes.

On Saturday, February 16, 2019 at 4:21:22 AM UTC-8, Bob Youngblood wrote:
I am trying to get away from the surge brakes and has anyone converted their trailer to electric brakes?? Thanks

Bob

I converted my cobra to Dexter Axle Torflex with electric brakes. I measured the axle bolt holes spacing, tire bolt scheme and distance from wheel to wheel. Purchased online from a trailer company they welded the brackets to fit. The easiest way is to take to a trailer dealer that carries Dexter Axles and have them replace the axle.
It was about 15 years ago as I remember $450 included shipping from Florida to CA. Call if you have questions.

Richard
www.craggyaero.com

What is your tow vehicle? You will need to wire in a trailer brake controller, easier to do on some vehicles than others.