Monday, July 6

Failsafe Left Turn

In aircraft structure, "failsafe" means an alternate path, so that if the primary path fails, the structure can still take the design load. It's a fancy way to describe what most long-range commuters eventually develop. Alternate paths.

This post describes a location with four failsafe paths, covering almost any combination of traffic conditions and even reducing delay due to railroad traffic. The ability to discover and develop failsafe turns and routes is one thing that gives a commuter a time and safety edge over a "visiting" rider. Local knowledge.

The location, headed home along Katy, about to cross Denton Highway (Hwy 377) and West Keller Parkway, FM 1709. It's on the border between North Fort Worth and Keller. It's a slow route by car due to the backups. I, on the other hand, experience few delays because my lower top speed has led me to come from a direction that is unclogged.

The sequence starts, going southbound, on Katy towards the four-way stop (4WS) at Keller Hicks Rd. I make a left (primary path) - UNLESS there's a southbound train that blocks the primary. In that case, I take route FS2 which will take me to a bike path that has an underpass under the tracks. Delay avoided. Cleverly, if there's a train, it blocks traffic both ways on FM1709, making the usually difficult stop sign (SS) turn from Katy to 1709 a trivial pursuit.

Freight trains are, however, not the norm and I usually stick to the primary route. Turning right with the green on to Hwy 377 (or a free right when the NB 377 LH signal turns green), I'm on SB Hwy 377 with only a few motorists following my lead. Most of the time, I bear left and take the primary LH turn to Lorinne. Sometimes, NB Hwy 377 traffic clogs up the left turn lane. If this happens, instead of hauling butt to get over to the left lane, I'll delay the lane change and wind up in the open LH turn lane at FS1. If things are really nasty, I may even go down to FS3 and turn left onto FS1709, where I'll have my own personal left turn signal. Such is rare, however.

If all else fails, and all affected roads are parking lots, I can take FS4, get off the bike on the other side of the intersection, and become a pedestrian to walk to Lorinne. I rode through that parking lot east of 377 twice, and do not relish the notion of emulating a human pinball. FS3 and FS4 may eventually disappear due to lack of use. Primary and FS1 take care of things most of the time, with an occasional FS2.

This photo sequence completely misses one feature - the parking lot where the subject of this post went to, and from where many of the photos were shot. I must say, I clean forgot to take that shot, so you'll have to content yourself with the label that shows the lot's edge. I never go that way on the bike. It does serve nicely, however, as a spot to take these pictures from.

Anyway, while this all looks complex, having the primary and failsafe paths predefined makes things very easy for me and reduces the stress level of getting past this busy location to the point that I actually look forward to this short little snippet of the route home. Without sneaking forward or doing other than waiting my turn, I get through this location at least five minutes quicker on my bike than I do by car. Top speed isn't everything when you have your failsafe turns lined up. This location also happens to be where I discovered "the Land Rover Rule," which has nothing to do with how quickly you can get through an intersection.


Steve A said...

The arrows are somewhat indicative, though not precise. On the primary route, I get over left quicker than when I decide to take FS1 as I don't want any of the followers to try passing as I'm moving into the LH turn lane - in this case, I'd prefer they just pass me in the RH lane. If I take FS1, I stay on the LH side of the RH lane until about a block before the turn, at which time I negotiate the rest of the way left and into the LH turn lane.

It's all a lot simpler than it sounds.

AND BEFORE anyone asks - "The Land Rover Rule" is: Before doing a bike maneuver I ask "would I do this in the Land Rover (sub the brand of your own motor vehicle)." If the answer is "no," the maneuver bears considerable review and reflections before it gets performed. Every time I go through this location in really heavy traffic, I just think, "remember the Land Rover rule." Works every time.

Rantwick said...

Hey, thanks Steve. I knew it was coming, but holy cow! Do you document stuff like that just for yourself, or did you just spell out for us what normally resides only in your head?

Rantwick said...

You're an Engineer all right. So was my Dad - it all seems very familiar somehow!

Steve A said...

I TRIED to describe/picture what resides only in my head. I had extra motivation with the ChipSeal/Doohickie "Difficult Left Turn" posts.

Engineers are what they are. It's why my WPCAT showed my LEAST promising profession was - "engineer."

My Dad was an engineer as well...

Steve A said...

You DID ask! Now you know why it took a bit. This post is a milestone. It's my first, unambiguously "VC" post, even though "failsafe turns" aren't really VC in and of themselves, but are more of a "regular route" item.

Doohickie and ChipSeal sorta pushed me over the edge, and I finally had the photos.

What I want to hear over at "Rantwick, eh?" are the latest devilish uses that tape measure's been put to...

Rantwick said...

Hey, don't try to absorb me into your VC measuring of everything club... that tape measure is back in my toolbox where it belongs.

If you were suggesting that I may be using the tape measure for something more "racy" allow me to assure you I have lost all my pep.

Steve A said...

VC means "Never having to say you're sorry..."

Doohickie said...

Interesting. I'm kind of familiar with that area; a friend of mine used to live just off 377.

You have all these alternates worked out in your head; my alternates are more organic. If I get to a point where traffic makes passage difficult, I just kind of flow around it.

On my commute home, for instance, I go primarily east and south. If something gets in my way when I want to go east, I just go a little further south, then cut east and just kinda float around the tight spot.

Having only a 7 mile (shortest distance) commute makes it easy to take little detours. My commute is usually just the 7 miles in the morning without too much variation (everyone is in "commute mode" and driving well-established routes), I ride as far as 12 miles home, either to avoid traffic or simply for the pleasure of taking a longer route.

Chances are good that at the end of the year my office will again move and my shortest distance commute will be 12 miles with a lot of unavoidable hills near the office.... we'll see how that goes.

Steve A said...

Having a 20 mile commute, one has a lot more TIME to ponder these things. You barely have time to wake up before you're at work!

Your current commute will prep you to step up to the 12 mile commute. My forecast is that you'll look back in wonder at your technique on the 6 miler. I will take great satisfaction in reading THAT post on your blog.

Myself, while it's only been 2 months on my new commute, I have found it making a major improvement in my riding under all circumstances.

No improvement, so far, in my common sense. Sorry...

Steve A said...

My "failsafe" turns started out organic. Then I noted the various traffic ebbs & flows more. Then I started taking advantage of them. Pretty soon, I did this post, with its confusing arrows and gibberish.

Bottom line. Start organic, then get methodical. My commute is long enough that I would do a lot of plotting and planning to consistently save a minute.

That is both an advantage and a disadvantage of being at the outer limit of one's practical daily commuting range.

Which brings up a post in the not too distant future - "Five Minutes to Go"

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