Race Strategy with Transponders

Most events don't require transponders. However, having a transponder helps with your race strategy. We run an "accumulated laps" race format where the pilot with the most laps after all the rounds wins. Our timing system announces your lap times so you can determine if you are on pace for your target lap count. A few seconds off on the last lap? Time to push on the next lap.

If you purchase directly from RcLapCounter they charge $38 plus shipping (usually $5). Make sure to specify that you want the FPV Drone version in your order notes. THIS IS VERY IMPORTANT!


GoDroneX was the exclusive tester of the I-LAP drone transponder from and is now a proud sponsor of our extreme drone sporting organization.

During our time testing the I-Lap drone transponder, we were amazed at the distance and accuracy of the timing system. All of our association members who have a transponder system use the I-Lap system. Why?

  • made in America
  • lifetime free upgrades
  • great support
  • attractive price
  • and most importantly . . . it works flawlessly.


Transponder FAQ's

How far will the I-Lap Drone Transponders go?
It is really a function of the sensor placement. The transponder signal is IR which means it has to compete with the sunlight. So when the sensors are in the sun the I-lap transponders work flawlessly to 6m. If the sensors are in the shade, distance is improved to 10m.

Is 10m signal distance enough?
GoDroneX's Finish gate is 2.5m' high and 3m wide. So the I-Lap transponder distance is double what is needed if the sensors are in the sun. GoDroneX's sensor tower keeps the sensors shaded, so the I-Lap transponder has triple the distance needed.

Why use an IR based system at all? Why not an RFID technology like Mylaps?
Two reasons. RFID systems are only accurate to 1m which is acceptable for race events on a flat horizontal plane like running, go karting and RC cars, but it isn't enough for aircraft. Secondly, expense. RFID systems can be 5x more expensive than the I-Lap system and RFID transponders are almost triple the cost of an I-Lap transponder. 

Why does GoDroneX have the I-Lap transponders aimed to the side? I have always seen them pointed up or down? 
Conventional wisdom had transponders mounted up. This evolved from RC car racing where cars pass under a sensor bridge. This works well for cars since they are on a flat plane when they go under the bridge. There is no "angle of attack" issue; cars drive on a flat surface. But this doesn't apply to drone racing as more skilled pilots will have more "angle of attack" than slower pilots. One of GoDroneX's core values is thought leadership. So rather than following conventional wisdom, we recommended to Craig, the owner of rclapcounter to aim the sensors to the side thus removing the angle of attack issue. This required the signal to travel 1m more. But with the drone version of the I-Lap transonders, we have way more distance than is needed.  He agreed with our thought leadership and now is recommending vertical sensor towers to new drone users of I-Lap. Another side benefit is GoDroneX's sensor tower becomes easier to setup and not susceptible to being blown in the wind if it was handing from above.

Is see three I-Lap transponder placement recommendations. What location does GoDroneX recommend? 
The best place is between the two lower plates. That provides maximum device protection and has the most propeller clearance.  But the main thing is to avoid the propeller plane.

What if a pilot has to make a roll correction as he goes through the Finish gate? Doesn't that take the beam off angle? 
Yes it does. First, a good course design for drone racing (or any racing for that matter) has the Finish gate on a straight away so pilots can drop their nose, gun it and keep the rotorcraft level. But GoDroneX has tested the roll issue and found that if the sensor tower follows our spec (see photo above) you can get accurate readings going through a 2.5m height Finish gate with a 30 degree roll.

What is the maximum speed that the sensors can handle?
The sensors have been tested with speed passes of 140 mph.

Is there polarity protection?
No. But if you plug the I-Lap servo plug into a Naze32 backwards, there is no damage. If you somehow manage to cross the positive and negative, you may burnout the internal voltage regulator so it is best to just use the servo plug into your flight controller.

Why use a timing system at all? What is wrong the accumulative method that GoDroneX uses?
Nothing is wrong with the accumulative method. This is how everyone starts out. It enables all pilots to get equal number of races in regardless of ability (a core value of GoDroneX). But it does require advanced frequency management as pilots switch who they are flying against every round. Managing frequencies is an organizational nightmare once you get past 7 pilots. Our GoRace cloud software greatly reduces the frequency management issue that beginning organizers face. In fact, that is the number one reason people join GoDroneX, our GoRace software.

The benefit of a timing system is that you are now simultaneously competing against the clock rather than other competitors each and every round. At first one might say this is a bad thing; after all we want to race each other. The reality is no matter what race format you use, you are racing against the clock. The fastest pilot wins. A timing system enables racers to compete against the entire field rather than who is in their heats.  Frequency management is much easier. Pilots get assigned to a run group usually based on either qualifying or how they did at the last event. So they set their frequency once, resolve any issue during practice and for the rest of the event focus on flying rather than interference. And finally pilots now get to race against people of their same ability rather than who the random number generator suggests with the accumulative method.

But the real benefit is that pilots hear their lap times since most race software has spoken voice functionality.   

So timed racing is a win / win / win / win. The racing is better for everyone; the racer, spectator, sponsor and organizer.