Layout Length Confusion

I whole-heartedly agree with Pete regarding the example in the manual. I know it takes someone's time to revise, but we should not have a 1km as an example. I had someone else set out a 1km, for the same reason as Pete's person.

I agree (with most).
I suggest we go with 300m or 1000 feet. I use a metric tape for all my cal courses.

Since most courses are metric, I suggest the example should be 300 meters(not 1km) for our manual.

This is just the example in the book and some may use 1000', which I as registrar always state it as 304.8 meters. Others give me some weird numbers like 1048', which I again convert to metric.

I'd like to chime in with the notion of using a 300 m or 1000 ft course. I understand the case for either one of those-- 1000 ft for avoiding conversion mistakes, 300 m for simplifying computations when measuring metric distances. I think we should put them both in there, not "favor" either one, and let folks choose whether metric or standard makes more sense for them. I'm a big fan of 300 meters but I see no reason to discourage 1000 ft.

As decided in a related series of emails, I will modify the example in the manual, changing the calibration course from 1 kilometer to 300 meters. I'll probably have this done within the next week or two. Meanwhile, I've already made two changes to the Steel Taping Data Sheet, as illustrated in the picture below. To get the new version, download the current Application Form Packet.

I've updated the sample measurement in the manual so it uses a 300 meter calibration course now. You can see the new version by either viewing the manual online or downloading the PDF at http://www.usatf.org/events/co...ertification/manual/

For these changes, I did some rewriting of the sections on measuring the calibration course and calibrating the bicycle (with related changes in a map and several data sheets), although I haven't changed the part about measuring the race course. This does introduce a slight anachronism. To avoid rewriting the section on measuring the race course, I needed to preserve the original 1982 measurement dates. But, in fact, the minimum calibration course length was still 800 meters in 1982. It wasn't reduced to 300 meters until 1987.

As noted earlier, I modified the Steel Taping Data Sheet to include the conversion 300 meters = 984.25 feet. I've also added this conversion in Appendix E on Metric-Imperial Conversions. This particular conversion would be exact if "feet" refers to the old "US Survey Foot" defined as 1200/3937 meter, but it's off by 2 parts per million if "feet" refers to the more modern "International" foot defined as 0.3048 meter.

Bob, I appreaciate the changes you made to the procedure manual. I was wondering why I had a couple odd distance cal courses last year.

MA11015JK CHURCH ST 2376.415' CALIBRATION COURSE

MA11017JK UNION-PORTER ST. 2140.16' CAL COURSE

I'll need to make sure that new measurers have the updated procedure manual. Thank you. -- Justin

Justin it's possible they measured from two fixed points like a storm drain or manhole cover. I've laid out a couple courses like that.

The saying goes that America and England are two countries separated by a common language. That might be applied to eastern and western Connecticut measurers, as well.
Pete Volkmar of Guido Brothers is based out of the eastern part of the state and does all his calculations in Imperial units. I'm in the western part (the "panhandle") and work completely metric. Generally not a problem as East is East and West is West and ne'er the twain shall meet. But when we do, oh boy!
I've measured a couple courses with Pete and when it comes time to compare our rides it's like apples and oranges. He tells me he has 13 miles 192.5 yards for a half marathon, and I reply I've got 21.0975 km. Eventually, though we work it out.
The one place it's caused trouble is on cal courses. Pete laid out a 1,000 foot course in Fairfield when he was down here measuring a half marathon in that town. A few years later a snowplow lopped off the end nails, so I re-laid the course, as a 300m. I did a measurement in the area last fall and went to the course to find the road had recently been repaved, but there were nails at the cal course endpoints. While calibrating I noticed the readings were way off what I normally get, which perplexed me until I used 304.8m as the distance, which made everything work out right. So, until the next snowplow or asphalt truck forces a redo, this cal course will remain part of the "Eastern Rite."

Speaking about losing nails:

1. We should remind folks, especially those who live in places where they have snowplows, to drive the nails far enough down so that the nail heads are below the level of the nearby pavement.

2. I've lost quite a few cal course endpoints over the years and this is taking me back to how I was originally taught to survey these courses (by A.J. Vanderwaal, a legendary figure around here). Here it is briefly:
-- You put a PK nail for each segment you measure-- not an an exact spot but within the range that you can measure with the precision that the tape offers. (this can vary, more on that in a second)
-- When you get close to your targeted distance you can calculate what you've already measured and what you need to add or subtract.
-- After the first measurement of the course you have a set of nails that you can measure to as you return for the second measurement.
-- Where you put the nail depends on the tape or chain you are using. If the tape goes up to its nominal distance, like 100 feet or 60 meters, then you want your nail safely short of that distance so you can measure it using the precision of the tape markings (usually, using interpolation, to 1/10 000 of a meter or 1/1000 of a foot). If it is a surveyor's chain, there is usually an extra foot marked beyond the zero foot mark, so you would use this.
A big advantage of this method: if an endpoint is lost there still may be a chance that some of the other nails are still there. You can quickly remeasure to re-establish the endpoint-- or, in a pinch, use the shorter distance for calibration until you get a chance to re-establish the end points.
This may sound more time-consuming than it really is. The return measurement goes really fast, you just lay down the tape, read and record it, and move on. Since you're dealing with odd distances you're unlikely to subconsciously "cheat" by trying to make it come out a certain way.
Here is a calibration course I laid out recently using this method with a 300-foot surveyor's chain. The map specifies the distances between nails and I'm hoping that will help for the next time they wipe out one end!
First Street 300 meters

Bob that's a good tip. I would think this could be used with Pete's 6-nail solo calibration course layout method and would work great.
I've never done this, but one thing I have done on my home calibration course is to put paint dots every 50m where the segment was measured during the initial layout. I find riding "dot to dot" helps keep me on a straighter line when doing my calibration rides (the course is on a road with no regular shoulder or curb, not even a side-of-lane line).

I like my full 1/2 mile cal course outside my house. I feel it gets me better measurements BECAUSE it is long.

I use a road bike and find it takes several runs up and down before the results start being very consistent. I think it takes time for the bike and me to warm up and start to work at a steady state.

It is only after a mile or two, (2 to 4 runs down the 1/2 mile) that the resulting counts are tightly grouped, so I often discard the first few and take the more consistent later runs, which invarably have less counts.

The other advantage with a long cal course, assuming it was accurately measured, is any error you do have is multiplied less when scaling up to the full course.

I've been unable to locate the nail at one end of one of my calibration courses (I think a plow got it, in spite of the fact I pound them as flush as possible and we only had one significant/plowable snow last year). Tonight, on the way to a race, I noticed they have repaved the road, wiping out any chance I had of finding even the remaining shaft and/or hole. Time to break out the steel tape, I guess.