This chapter defines the evidence, measurements and calculations required to verify soaring performances. Annex C gives examples of ways and means by which this may be done, such as the calculation of distances, and the method of GNSS flight recorder data analysis.
The following is a list of all the flight data that needs to be gathered or measured to provide evidence of the completion of any soaring performance:
a. declaration (1.3.2)
b. start point (1.1.8)
c. start time (1.2.1)
d. start altitude (1.2.2)
e. turn point(s) (1.1.10)
f. finish point (1.1.12)
g. finish time (1.2.3)
h. finish altitude (1.2.4)
i. maximum altitude (1.4.2a)
j. gain of height (1.2.8)
k. flight continuity (4.3.4)
Different soaring performances will require different subsets of this list.
For each flight, certain information is required to be recorded before the flight in order to ensure that proof of the soaring performance is available after the flight. This data, including waypoints (e) is known as the declaration. For some performances, some data is not required, but the Official Observer must ensure that all required data is recorded.
The information shall be written on a single sheet of paper or board, or recorded in the memory of a flight recorder prior to the flight. For world records only the latter applies.
a. Date of flight
b. Name of pilot in command/name of crew (if any)
c. Type and registration of glider
d. Type and serial number of barograph or flight recorder
e. Way points and the sequence to be flown, start, turn(s), finish/goal as applicable to the specific soaring performance * (See also 4.2.3)
f. Date and time of declaration
g. Signature of pilot in command **
h. Signature & name of OO, with date and time. **
* not required for free distance records
** not required for electronic declarations
4.2.2 Declaration validity - missed turnpoints
a. The last declaration made before takeoff is the only one valid for the flight, but a concurrently flown and different competition task is allowed.
b. If a declared turn point is abandoned, a closed course flight may still be claimed from the resulting shorter course provided that the turn points achieved are in the sequence specified in the
declaration.
Therefore, no turn points after a missed turn point may be claimed. See Annex C for examples of soaring performances allowed following the abandonment of a pre-declared course.
4.2.3 Use of waypoint lists in pre-flight declarations
Where waypoints are identified in the declaration by abbreviations or codes rather than by exact WGS84 lat/long or by exact geographical points, the key to the abbreviation or code must be attached to the claim. The key shall include the exact WGS84 lat/long or be the exact geographical point against each abbreviation or code used in the declaration, and it must be shown to have existed before the flight concerned.
A barograph or device incorporating a barograph must operate throughout the flight. The barogram so produced must provide indisputable verification of flight continuity (see 4.3.4) and of all altitudes critical to the soaring performance. The device may record parameters in addition to barometric pressure and time if it is suitable for the purpose (see 4.4). If data is recorded at intervals, the sampling rate setting must be no slower than once per minute.
For flight recorders, timing and pressure altitude data will be taken at the boundary of the observation zone interpolated between the times of valid fixes; or for a start or finish, this data may be taken from the fix in the observation zone which is most favourable to the pilot. See Annex C para 9.2.
The landing location must be certified by one or more of the following:
a. By an OO arriving soon after the event and there is no doubt about the position of landing or,
b. By two witnesses (see 5.2.3d),
c. By position data from a flight recorder (but see also 4.6.4a(ii)).
Where the soaring performance is required to end at a declared finish point, the goal will be achieved if:
a. The landing point is within 1000 metres of the declared finish point or,
b. If the finish point is an airfield, the landing is within the boundaries of the airfield or,
c. Satisfactory evidence is produced showing that the glider was in the observation zone and within 1000 metres of the finish point,
d. A finish line at the goal is crossed.
e. For any type of closed course goal flight where a start other than release or a start line is used, the glider must exit the start point OZ within 1000 metres of the declared start point.
There must be evidence that the glider did not land or a means of propulsion was not used during the claimed soaring performance. An interruption in the barogram data will not compromise proof of flight continuity provided that the OO and NAC are convinced no critical data is missing and that the evidence for flight continuity remains indisputable.
a. The five hour duration flight (2.1.1b and 2.1.2b) does not require a barogram to prove flight continuity where the flight is made under the continual surveillance of an OO.
b. In the event of failure of the pressure altitude recording in a flight recorder, evidence of flight continuity may be assessed from a time plot of GNSS calculated altitudes provided the rule on the
setting of sampling rates is followed (4.3.1).
Absolute altitude, gain of height, and start altitude must normally be verified from atmospheric pressure data recorded by a barograph. External measurement (see 4.7.1) may be used only when the required accuracy can be verified.
Time, geographical position, altitude, and means of propulsion are flight performance data which must be either recorded or measured for some or all types of flights. Using this data, calculations of distance, speed, duration, gain of height, altitude difference, height penalties and start height may be done.
4.4.1 Calculations for distance and speed
For world records, distances between two points in excess of 1000 kilometres, and in any case of dispute over a distance, the distance flown is deemed to be the length of the geodesic line joining the start point and the finish point or, if there are turn points, the sum of the geodesic lines for each leg of the course, corrected as in 1.2.11. See Annex C, Appendices 2 and 3.
a. EARTH MODEL TO BE USED
For the purpose of the calculation of FAI geodesic distances, the WGS 84 earth model shall be used. See also Annex C, Appendix 2.
When calculation of the exact distance is not critical, less accurate methods may be used. See Annex C , para 1.6b.
b. GEOGRAPHICAL COORDINATES OF WAY POINTS
NACs are to specify procedures for recording the geographical coordinates of way points from maps of their national territory using geographical co-ordinates such as Latitude and Longitude, map grid, or national grid (if such a grid exists for the area
concerned).
c. MAP SCALES
Measurement of coordinates of way points should be from a map with a scale at least as detailed as 1:250,000, and preferably 1:50,000 (if such a map exists which includes the way point concerned). For
records, if a scale less detailed than 1:50,000 was used, the NAC should be able to show that co-ordinates were taken from the most accurate map available for the way point concerned.
4.4.2 Loss of height and application of the height penalty
a. For distance flights of more than 100 kilometres, where the loss of height (1.2.7) exceeds 1000 metres, a height penalty (1.2.12) must be subtracted from the length of the course to give the official distance.
b. For distance flights of 100 kilometres or less, a loss of height exceeding 1% of the length of the course will invalidate the soaring performance.
c. For speed and duration flights, a loss of height exceeding 1000 metres will invalidate the soaring performance.
4.4.3 Flight data requirements
The minimum flight data required for each type of soaring performance is given in Table 2.
| Soaring Performance |
Measurements | | | Calculations | ||||||
|---|---|---|---|---|---|---|---|---|---|
| Time | Position | Height | MoP | | | Distance | Height | Speed | ||
| Distance | x | x | x | x | | | x | x | ||
| Goal | x | x | x | x | | | x | x | ||
| Duration | x | x | x | | | x | ||||
| Altitude | x | x | x | | | x | ||||
| Gain of height | x | x | x | | | x | ||||
| Speed | x | x | x | x | | | x | x | x | |
The minimum accuracy of measurement and calculation required for each type of flight data is given in Table 3. Any inaccuracy in ameasurement or calculation is to be interpreted to the maximum
disadvantage of the pilot.
| Soaring Performance |
Measurements | | | Calculations | ||||||
|---|---|---|---|---|---|---|---|---|---|
| Time | Position | Height | MoP | | | Distance | Height | Speed | ||
| Distance | 1 min | 500 m | active | | | 1 km | 30 m | |||
| Goal | 1 min | 500 m | active | | | 1 km | 30 m | |||
| Duration | 1 min | active | | | 30 m | |||||
| Altitude | 1 min | 1% | active | | | 10 m | ||||
| Gain of height | 1 min | 1% | active | | | 10 m | ||||
| Speed | 5 sec | 500 m | active | | | 1 km | 30 m | 0.1 km/h | ||
Precision of measurement
Care should be taken to correctly assess the precision of measurement devices so that an invalid level of accuracy is not introduced into calculations. See
Annex C for more information.
4.4.5 Combinations of measurement methods
Any combination of the measuring methods is acceptable for the various types of flights, provided the minimum requirements for accuracy of equipment in paragraphs 4.4.3 and 4.4.4 are fulfilled.
Each method used must comply with this Code as if it were the only means of proof employed.
4.4.6 Timing device calibration
When used, clocks and other time recording equipment shall be checked against official time signals both immediately before and again after the flight, covering a period of at least three hours. Any error found shall be taken into account and rounded up in the calculations. The GNSS time recording from a flight recorder may be used as an official time signal.
4.4.7 Barograph calibration
period
Barograph calibrations are required to ensure that the measurement of barometric pressure and time are checked against, and corrected as necessary, to official standards. For altitude and gain of height
records, both (a) AND (b) calibrations below are required, and the least favourable calibration of the two shall be used making the calculations for the record. For badges, start height verification,
and altitude difference calculation, either (a) OR (b) are required.
a. PRIOR TO THE FLIGHT
The calibration used must have been performed within 12 months prior to the flight or, for IGC-approved electronic barographs and FRs, 24
months.
b. AFTER THE FLIGHT
The calibration used must have been performed within one month after the flight or, for IGC-approved electronic barographs and FRs, two months.
When absolute altitude (not altitude difference) is to be determined, the altitudes reached during a flight from the barograph evidence must be corrected for a height error arising from the actual atmospheric pressure of the day compared to the standard atmosphere.
The method of arriving at a corrected altitude is given in Annex C.
Time data requirements may be fulfilled by any of the following measuring methods:
a. By direct observation from the ground by an observer with direct access to approved time measuring equipment (e.g. a synchronised timepiece). If a timepiece displaying only minutes is used, 59
seconds is to be added to each duration measured to allow for the possibility that the reading was taken just before the minute changeover. Pilots and OOs should use timing devices with outputs in seconds whenever possible.
b. With a barograph, to measure time differences (except for speed flights),
c. With a time camera, to measure time differences (except for speed and duration flights),
d. A recording device with correct real time input, such as a flight recorder.
a. Evidence of timing and time recording of flights must be under the control of an OO. Time recording equipment carried on board a glider must be capable of being physically or electronically sealed and, where a human action is required, shall be sealed and unsealed only by the OO.
b. The equipment must be positioned so that the time parameters cannot be altered by the pilot or passenger during the flight.
c. If a means is provided for the pilot to make inputs into a device for remote recording of flight events, such inputs must be confined to functions not critical to the validation of the flight.
For example, it is permissible for a pilot to make a mark on the time base to register an event such as a particular position, or in GNSS systems to change the sampling rate in flight.
A flight which continues beyond the hours of legal daylight in the country concerned shall not be validated, except where the glider and pilot comply with the laws of that country for night flight.
Flight position data requirements may be fulfilled by any of the following measuring methods:
a. By direct observation from the ground for start, turn, and finish points,
b. Satisfactory photographic evidence from a camera in the glider;
c. Satisfactory data from a flight recorder in the glider.
4.6.2 Position evidence - general
a. POINT OF RELEASE
Evidence of point of release may be provided by the pilot of the towplane or the person supervising the ground launch of the glider.
b. HEIGHT OF RELEASE
The height of release shall normally be obtained from a barogram. External measurement (see 4.7.1) may be used only when the required accuracy can be verified.
c. CROSSING A START LINE
(i) When the start line is controlled by observation from the ground, visual observation of a crossing in the direction of the first leg at an altitude of not more than 1000 metres above the line.
(ii) When using flight recorder evidence, by clear proof that the start line was crossed in the direction of the first leg.
d. CROSSING A FINISH LINE
(i) When the finish line is controlled by observation from the ground, the nose of the glider crosses the finish line unassisted from the direction of the last leg at a height of not more than 1000 metres above the line.
(ii) When using flight recorder evidence, by clear proof that the finish line was crossed from the direction of the last leg.
e. WAY POINTS
Way points should be of such a nature that they are easily recognisable from the air. Where photography is used, way points shall be point features and should be selected to make interpretation of photographs easy, even on photographs taken in
difficult light conditions such as low contrast. Where a flight recorder is being used for verification, the way point coordinates do not need to represent a point feature on the ground.
f. OBSERVATION ZONE
Evidence is required that the glider was within the observation zone (1.1.5) of a way point used during the flight. This may be collected by using one or more of the following
three methods:
(i) Direct observation, in which the glider is positively identified as being within the observation zone by an OO on the ground at the turn point. Magnification and tracking devices may be used.
(ii) Photographic, where the pilot presents a satisfactory photograph taken from within the observation zone in accordance with the rules for photographic evidence below.
(iii) Flight recorders, where (in accordance with the IGC rules for the use of this equipment (see 4.6.4), the data record shows incontrovertible proof that the glider was in the
observation zone, with one position fix recorded either exactly on the position of the waypoint or within the observation zone, or else a straight line drawn between two consecutive valid fixes crosses
the observation zone. See Annex C para 4.6 and 7.1c.
4.6.3 Photographic position evidence
Cameras can be used on badge flights to provide evidence of position and generally substantiate the soaring performance by means of a sequence of photographs on a single length of film. There shall be proof that all photographs were taken from the glider on the flight concerned and that turn point(s) were photographed between the start time and finish time.
a. PHOTOGRAPHIC CONTROL METHOD
The following method shall be used:
(i) Mounting in the cockpit
The camera must be held in fixed mountings in the cockpit so that every photograph will show the wingtip. The lens housing should be positioned inside the canopy or camera window so that the random line mentioned in (iii) below will show on the film (this does not apply to open-cockpit gliders). See Annex C para 3.4.
(ii) Sealing the camera
The camera must be sealed unless the same OO is controlling both the pre-flight photograph(s) and the processing of the film, in which case sealing is not necessary. When a time recording camera is used
to supply time evidence, it must be sealed by an OO before the flight in such a way that the film cannot be removed and the time adjusting mechanism cannot be accessed until the seal is broken by an OO after flight.
Just prior to takeoff an OO shall mark the outside of the canopy or window across the front of the lens with a random line and display the flight declaration for the pilot to photograph with the camera
installed.
The random line should be dark or opaque and at least 3 mm wide if it is to show on the image.
(iv) After flight
Following landing and the completion of the photographic sequence, an OO shall take charge of the film and have it developed. Every effort is to be made to preserve the film as a continuous strip.
However, if it is cut or broken while out of control of the pilot or OO, this evidence remains valid if close examination of the pieces show that they form the original continuous length of film. An OO shall describe the circumstances under which the film was broken or cut.
b. PHOTOGRAPH SEQUENCE
The film shall contain photographs in the following sequence:
(i) the pre-flight clock synchronisation photo(s) if a time camera is used, (see 4.5.1c and 4.5.2a),
(ii) the declaration,
(iii) at least one photograph showing indisputable evidence of the presence of the glider in each of the observation zone(s) of the way point(s) used, in the correct sequence,
(iv) the glider on the landing field with surrounding features and its registration markings appearing clearly on the photo, or the above declaration with landing time added.
(v) the post flight synchronisation photo(s) if a time camera is used.
Photographs in (ii) and (iii) above must show the shape of the canopy mark (see 4.6.3a(iii)) on the film image. Additional photos which may have been taken after the declaration and before the landing must also show the canopy mark.
4.6.4 Flight recorder (GNSS) position and other evidence
All flight recorder evidence must be produced by an FAI/IGC approved system. The WGS84 Geodetic Datum shall be set for all Lat/Long data that is recorded and transferred after flight for analysis. Data
must be produced from a flight recorder that has an IGC-approval for the type of soaring performance that is claimed. Any FR used on the flight must comply with the conditions of its approval. The approval documents for each type of recorder will be posted on the FAI gliding/gnss web pages and shall specify procedures to be used, any limitations, and advice on its use. See Annex B Chapter 1.
a. FLIGHT RECORDER CONTROL METHOD
The OO shall familiarise himself with the terms of the approval for the GNSS and flight recorder equipment concerned. See Annex C, Appendix 6 para 2.3. There must be incontrovertible evidence, independent of the FR data, that the FR from which the flight data was taken was in the glider flown by the pilot during the claimed soaring performance.
(i) Before the flight
The OO shall sign the pilot's written flight declaration, except where the declaration is stored electronically in the flight recorder (1.3.2). The OO shall enter a secret code into the flight recorder if the IGC approval for the
equipment requires this. The flight recorder system shall be placed, configured or sealed in such a way that it will be physically impossible to operate any controls other than those specifically allowed for use in flight; and to connect or disconnect any device to the flight recorder system other than in accordance with the IGC approval for the equipment. The method(s) of sealing, if any, shall be specified in the IGC approval for the equipment.
(ii) Takeoff and landing
An OO shall ensure that there is evidence for the times and points of takeoff and landing, pilot(s) names, glider type and registration, and the type and serial number of the FR for flight evidence. This evidence shall be independent of the data produced by the FR. See Annex C para 11.3.
(iii) After flight
After landing, the flight data shall be transferred from the FR to a memory device acceptable to the NAC via a PC or other device in the manner specified in the IGC approval for the equipment. The OO shall check any seals which were applied before the flight. The flight data shall then be sent to a person approved by the NAC to make the analysis. This may be by physical dispatch of the memory device or by e-mail if acceptable to the NAC. For world record claims, a copy of the .igc file is to be sent to the FAI within 7 days along with the notification of a claim (see 3.2). This process must be performed for all FRs carried during the flight.
b. DATA ANALYSIS
Analysis of the flight data shall be performed by a qualified person, approved by the NAC, whose duty is to ensure that the appropriate evidence is present to verify the attainment of way points, heights, times and position. Analysis guidelines are in Annex C. Where there is more than one FR, the one holding the last declaration (the primary FR) shall normally be used for analysis. If the primary FR has a failure, a secondary FR may be used for verification provided it has the same declaration and flight data details. A difference in the declaration on a secondary FR from the primary FR could be grounds for refusal to accept any claim from that flight.
If the soaring performance qualifies for a badge or record, the following shall be forwarded to the NAC:
(i) The original data on the memory device (the first copy) storing the flight data for each FR. This must include the data file in *.igc format, and the file in its original format (if different) as transferred
from the flight recorder immediately after landing.
(ii) The appropriate claim form(s), including OO's evidence that manually recorded times and exact locations correspond to the equivalent flight recorder data.
(iii) For free record flights, the achieved way points shall be determined from the flight recorder evidence and specified in the claim for the record. The flight recorder "pilot event marker", if incorporated, may be used to indicate the desired waypoint position(s).
(iv) Any other measured data and/or auxiliary material required by a NAC to support the mandatory evidence. See examples in Annex B, Appendix 1.
Altitude data requirements may be fulfilled by any of the following measuring methods:
a. A barogram,
b. Optical measurement from the ground (e.g. a suitable height frame or theodolite),
c. Radar measurement from the ground,
d. For continuity of flight purposes only, the GNSS altitude output of a flight recorder.
4.7.2 Altitude control methods
For altitude recording other than by external measurement, a barograph or flight recorder must be carried in the glider. Any marking of the barogram during flight shall be done by remote control, not by direct access to the barograph itself. The barograph shall be placed in the glider in such a way that no part of the barograph is accessible to the pilot or passenger during the flight.
The pressure altitude recording system in a flight recorder is a barograph and must comply with other rules in the Code for barographs and their calibration. Altitude control methods for flight recorders are the same as those used for position evidence (see 4.6.4).
a. BEFORE TAKEOFF
(i) Mechanical barographs
The OO shall make an identification mark on the barogram paper/foil and then seal the barograph.
(ii) Electronic barographs
The OO shall seal the barograph and then enter a secret multi-character code into the barograph memory before flight (a second entry of this code shall be required to retrieve the stored data). This step is not required if the barograph stores continuous date and time data which cannot be altered without the fact of such alteration being automatically reported on all data printouts from
its memory after such alteration, and the OO is able to verify the date and time of the takeoff and landing of the glider on the flight concerned.
b. DURING THE FLIGHT
As soon as possible after release, the pilot of the glider should ensure that a low point is indicated on the barogram to clearly indicate the start of the soaring performance.
c. AFTER THE FLIGHT
(i) The OO shall take control of the barograph, and ensure that its seal is secure and that the barogram has the identification mark placed on it prior to takeoff. The information required in paragraph
6.1 may then be added to the chart.
(ii) For electronic barographs, an OO must either supervise the transfer or printing of data from the barograph while it is in the glider, or supervise the removal of the electronic barograph from
the glider and shall then take charge of it until the flight data is printed out. The OO then confirms that the date and time on the printout is correct and that the date and times of the altitudes and
other flight data recorded and printed out correspond to the date and times of the flight concerned, and correspond with other relevant aspects of the claimed performance.
4.8.1 Means of propulsion evidence
The requirement to record data on the use of any MoP may be fulfilled by any of the following methods:
a. The data is recorded by a MoP recorder, or
b. By direct observation from the ground that the MoP has stopped,provided that there is no means of restarting it, or
c. By a seal applied to the MoP in such a way that the generation of forward thrust by the MoP always results in breaking the seal.
d. For World Records, where a MoP recorder is required, it must be incorporated as part of the flight recorder.
a. With the use of an MoP recorder:
The MoP recorder must be sealed and opened only by an OO, and mustnot be accessible to pilot or crew during flight, except where it is an IGC approved flight recorder operated in accordance with the IGC
approval.
b. Without the use of an MoP recorder:
(i) Before takeoff, the MoP may be sealed by an OO as in 4.8.1c (and the OO shall certify that the seal was intact after landing), or
(ii) The MoP may be rendered unusable by removing an essential part of the engine or the propeller (and the OO must certify that this was done), or
(iii) The MoP may have a mechanical lock applied to the retraction system that cannot be unlocked until after landing.
c. For World Records the MoP recorder must be of a type (see 4.8.1d.), which records the use of the MoP automatically, without any special action by the pilot and it must not be capable of being switched off during the flight, nor require a special type of mounting within the glider to enable it to operate.