Ham operators in my area work a lot of drills and events over the course of a year. (We have well over 1000 hours in on events, and that does NOT include Field Day.) We conduct a “hot wash” after every event to see if we can improve on anything. Remember, just noting what went wrong isn’t a “lesson learned,” it’s a “lesson identified.” You haven’t learned anything until you do something to fix it, and it works. You can’t do that without some sort of after-action review.
We’ve learned that bikes are very useful for the larger events. They provide more mobility than automobiles, use less fuel, and are often less intrusive and disruptive. Of course, they also take longer to get from A to B, and believe me, the weather isn’t always entirely conducive to being in the open. But the advantages outweigh the disadvantages in most cases, so we include them in our event plans.
Let’s use a recent marathon as an example. This event actually combined a 13.1 and 26.2, and it was a qualifying event for the Boston marathon, so we had thousands of runners and supporters on site. It was less than a week after the bombing at the Boston run, so things were a little more tense than usual. There was a lot of focus on situational awareness — knowing where the walkers and runners were at any given moment.
Tracking the lead runners is actually not hard. There is normally a lead vehicle (truck or car, I’m not sure something like a Gator will keep up). Because the lead runners for both the half and full runs are pretty fast, that works well. Unfortunately, that’s less true for the other end. The trailing walkers/runners are a lot slower and stop more often. We decided to have two bikes equipped with APRS gear at the end of each of the runs to track the trailing edge. Bikes seemed the best choice for several reasons. First, we have a few local hams who are dedicated bikers who have reliable installations on their rides. Second, a reasonably skilled biker can ride VERY slowly — I can drop under 2 mph on my mountain bike without a second thought, and the other bike was a tricycle recumbent (the fabled Wheeled Barcalounger). Third, they are allowed on sidewalks and walking trails, which turned out to be important for this particular event.
APRS coverage was provided by a local digipeater set to the event frequency — we didn’t want to use the standard frequency due to the high number of packets sent during the day. The local digi also gated the packets to the APRS-IS backbone so that it was available to race officials and public service by smart phone. In addition, we used HSMM-MESH(R) to make sure that a dedicated display was available in the EMA mobile command post. NCS had a digital position that made sure that all water stops and other labelled points were beaconed as objects regularly.
The tricky part was getting the bike rigs set up. Signals were chiefly good, even with just a rubber duck — but only if the radio was NOT right next to the rider’s body! But we did have trouble with some of the more subtle settings, which caused some problems for NCS. The digi was able to receive all packets, so race officials didn’t share this problem. (That was rather serendipitous.)
Here are my recommendations for APRS settings for these events. They apply primarily to the bikes and lead vehicle, but they will work for the more stationary operators as well.
- Turn SmartBeaconing (R) (or GeniusBeaconing (R), whatever you’re using) OFF. You’ll actually want to ping at a regular rate. This is especially true for the chase bikes. SmartBeaconing bases its ping times primarily on speed and “corner pegging.” GeniusBeaconing seems to work mostly from position error. In both cases, your chase bikes are going too slowly for this to provide any reasonable update rate. Even if you change the algorithm parameters, you’re not going to get a good result. Two to five minutes between pings works very well. We used three minutes at one event.
- You must turn off both proportional pathing and the decay algorithm, if any. Both were created to reduce traffic in crowded areas, back before we had sophisticated algorithms. Unfortunately, that’s the opposite of what you want at these events! Proportional pathing actually changes the path setting between pings. So if you are set to WIDE2-1, you’ll get a ping for WIDE2-1, then one for RFONLY, then a WIDE1-1, then RFONLY…then the cycle repeats. Our problem was that NCS wasn’t getting all the RFONLY signals. A decay algorithm actually increases the ping time if you aren’t moving…this is less critical, but turn it off anyway.
- If your infrastructure supports it, move large events to an alternate frequency. We used 144.990 (+600 kHz from the national standard). This will keep non-event pings off everyone’s displays, and doesn’t flood non-participants with irrelevant packets.
Here are some other considerations:
- WEAR A BLOODY HELMET. Seriously, there is no excuse for not having one. I know a lot of people consider them too restricting, or too hot, or even too “not cool, man.” I’ve even heard one addle-pated twit suggest that they make bikers less safe. Trust me, they work, and you’re not likely to find circumstances at these events where they won’t.
- I highly suggest a mirror. You’ll hear apocryphal stories about how mirrors are dangerous because shards might fly into your eye or pierce your brain or vote Communist…ignore them. I couldn’t find a single, documented case of a small mirror being a problem that didn’t involve someone mounting it particularly stupidly. You can live without one, but it sure helps.
- Dress in layers. The first marathon event was bloody cold! It eventually warmed up, but holy carp…it was nasty. Layers will help you stay warm AND dry.
- Bring your own water and snack bars. We’re usually nicely supported by the race staff, but we don’t depend on it.
We’ve had a lot of success with this at recent events. I encourage you to give it a try.