Last Updated April 15, 2009
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Revision 1, September 2000

1. The yacht shall be propelled by wind energy only.

2. The yacht shall have no stored energy other than for instrumentation, i.e. small batteries for speedometers or GPSs. Energy shall not be accumulated by pumps or generators driven by the wheels, ground, wind or sun or any other source. All controls on the yacht will be operated directly by the pilot with out consumption of stored energy (other than the pilots breakfast).

3. The yacht shall start from a dead stop without assist from any external source other than humans, on foot, pushing.

4. All points of the course shall be within 3.3 feet (one meter) in elevation.

5. The pilot and crew of a yacht attempting a speed record shall release and hold harmless the North American Land Sailing Association (NALSA), its officers, agents, and members from any and all liability for any damage or injury to their persons or property sustained in such attempt, whether such damage or injury be due to negligence of said association, its officers or any other cause. The pilot shall accept the responsibility for any damage done to NALSA's, land owners' or observers' property. It is the sole and exclusive responsibility of the pilot to decide whether or not to make his attempt.

6. All official speed measurements shall be taken in a scientifically valid method approved by the NALSA board. In addition to this primary measurement, at least two secondary measurements shall be made by separate systems. All measurement systems will be calibrated. A plan that addresses the calibration and accuracy of all measurement methods as well as the identification and elimination of spurious data will be given to the disinterested observers prior to the speed measurements session. This will be called the Measurement Plan. The primary measurement will not be adjusted to take into account the angle of the yacht relative to the measurement device.

7. Two disinterested observers, one of whom shall be a NALSA officer, director or someone approved in advance by at least two members of the NALSA Board to represent NALSA, shall observe the speed record attempts and perform any off-board measurements. Their role is to assure that the measurements are scientifically and ethically valid. At least one of the observers will be fully competent to operate and calibrate all the primary and secondary measurement equipment.

8. NALSA Review and ratification: A report of the data from the record setting measurement session will be submitted to the NALSA Board. It will cover the measurement and calibration data from all measurement methods, commentary on spurious data, significant deviations from the measurement plan as well as anything else that is thought to be relevant. A copy of the original measurement plan will be attached. The original data record as well as all measurement data and other supporting information will be included. The observers will review this report before submission to the NALSA board. The observers will add a report of their observations especially regarding the scientific and ethical validity of the potential record setting run. The NALSA Board shall review the report and decide if the measurement data is valid. It shall request any supporting information that it believes will be of help. The Board's decision is final.

9. The record speed must be more than one mile per hour (1.6 km/hr) above the record to be beaten.


No specific rules or techniques have been adopted by NALSA for the setup or calibration of speed measuring devices. It shall be the contestants' responsibility to convince the NALSA Board of Directors that the measurements are scientifically valid. The following discussion will give the contestant guidelines for things the board will be considering in validating a claim for a world speed record.

The primary method must have an accuracy of plus or minus 0.5 mph (0.8 km/hr) or less. Accuracy is defined as twice the combined measurement uncertainty of the measurement system (ie at 95% confidence). At present the only methods that are acceptable are high performance GPS, radar and timing traps. Other methods will be considered by the NALSA Board but must be approved by the Board prior to being used for the primary measurement.

A high performance GPS with data logging is the preferred method.  It is very accurate and records a great deal of supporting data.  Being an onboard system avoids having to sail close to a measuring station at high speed.  A suitable GPS system must have a data storage device that will allow it to record speed, time, position, velocity and relevant quality parameters every second during the speed runs (the combined system must be able to output and record NMEA sentences ‘GGA’ and ‘VTG’ at one hertz).  At present this will require a sophisticated GPS unit.  Differential GPS is preferred but not required. Inexpensive GPSs are not currently designed to output velocity data and do not have the necessary processor speed and accuracy to be used as the primary measurement method. The top speed will be the average over three consecutive seconds.  The NALSA board or observers may have the unit inspected by their expert at any time.  The measurement plan must address calibration, measurement uncertainty, handling of the GPS equipment (eg: to assure it does not get a ride in a fast car in the middle of a measurement session), and handling of the data to assure that false data can not be substituted.  It is preferred that the GPS be used without filtering (smoothing of the raw data before recording it).  If any filtering is present it must be thoroughly explained.

Radar is the simplest to use: requiring minimum setup, is easy to calibrate and has historically proved accurate in NALSA use. Calibration should follow manufacturers guidelines for proper use of the tuning fork. The simultaneous use of more than one gun is desirable.  Recording multiple readings from the primary radar gun during each run is preferred. This provides evidence against a spurious maximum speed reading.  Special consideration needs to be given to address the potential for spurious readings related to vibrating parts of the boat in view of the very short duration of the radar measurement (0.04 sec).

If a timing trap is used as the primary measurement, a commercial unit designed for measuring speed events (such as those made by TAG Heuer) is preferred. Any timing trap setup must have a demonstrable an overall accuracy of plus or minus 0.5 mph (0.8 km/hr). This includes all factors affecting the sensing devices, the timing device and the surveying method used to layout the trap.

In addition to the primary measurement, at least two independent secondary measurements of the maximum speed should also be made. This is to verify the general validity of the primary measurement. Suggested secondary methods include speedometers, radar, GPSs, video taping, etc.  The observers may add their own secondary measuring devices.   Secondary methods must have a means for recording the maximum speed. The secondary methods should be calibrated in a manner similar to the calibration for the primary measurement method but should not be calibrated with the primary measurement equipment.
The observers should verify calibration of all primary and secondary measurement methods immediately after completion of a potential record breaking session. An analysis of the sources and likelihood of spurious measurement data for the primary and secondary measurement methods should be made. For example if the course is near a highway and radar is being used, the measurement should be done so that it does not pick up a vehicle on the highway. With GPS , fixed position ‘velocity’ and signal quality needs to be verified.  With a timing trap, some analysis should be done to verify it does not sense false interruptions.

A record speed will be reported to the nearest 0.1 mph (0.1 km/hr).  All calculations and conversions will be done with at least five significant digits.  The recommend conversion factor for miles to kilometers is 0.62137 mi/km.

If you are planning a record attempt we encourage you to establish a dialog with NALSA early in your project so we can assist you in complying with these regulations.  See for an example of a measurement plan and final report.

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