Access Keys:
Skip to content (Access Key - 0)
All CIMA spaces


This space

04 - CZE - Basic rules for tasks

Proposal from

Vladimir SILHAN (CZE)

Proposal title

4.29.2   Basic rules for construction and designing of the competition tasks

Existing text

4.29.2 The tasks to be used shall be approved by CIMA (S10 A4) and precisely set out in the local regulations together with the method of scoring.

New text

4.29.2   Basic rules for construction and designing of the competition tasks

The first liability of the task designer and championship director is to assure the safety of the task. There shouldn’t be requested any unsafe procedures and initiations of collision situations between competitors and competitors and any other aircraft.

Any incidents and collision situations must be avoided as possible. Preferable solution is reservation of relevant part of airspace for competition flights and sufficient steps between following competitors.

Starting lists shall be set from fastest to slowest airplanes and if some change in starting order will be needed, sufficient distance preventing of a collision situations or/and team cooperation must be respected. The minimal time distance between two following airplanes is two minutes.

Diversion of a collision situation shall be no reason for loosing of score or penalisation of competitor, if no advantage had arisen by this diversion and diversion of collision situation was announced to competition director immediately after landing and manoeuvre will be visible and checkable in the track log.  

(Reason - pilots mustn’t be motivated for risky decisions and flying)


Navigation tasks: Competition maps and detail instructions with specifications of locations of turn points and gates, legs distances, photos and marker catalogue and all other detail instructions will be given to competitor in the aircraft in the pre-flight quarantine in the beginning of planning time. All distances used in the evaluation process must be measured from the same map, which will be given to competitors for flight. Calculation of distances (by mathematic methods from latitudes and longitudes) is possible only in the case, when lengths of legs are written in instruction for competitors. Measuring will be made with precision for 0,5 mm in the map and rounded to one decimal of kilometre. Methods of measuring of the lengths of a track described in chapter 5 are valid only for records, no for competitions and championships.

Reason: competitors shall have the same possibility for measuring as task designer had. Pilots haven’t possibility to get latitudes and longitudes with accuracy for meters and they haven’t computers for calculation of the correct distance. Because only maps are given to competitors, or distances must be announced to competitors, or measuring must be provided by simple method feasible in limited time with limited equipment and comfort. This is something absolutely other than records, where pilot haves non limited time and equipment for pre-flight preparation. Gates and turn points shall have following dimensions and tolerances:

  • Starting gate and finish gate shall have radius 2 mm in the map.
  • Known time and track gates and known turn points shall have radius at least 1 mm in the map.
  • Known gate or known turn point must be located in the place, which is drawn in the map. The centre of the gate or turn point don’t be defined as large object, for example castle, cathedral, large traffic ring, pond, lake etc. If using of like this object is necessary, shall be given sufficient tolerances (100% score will be given to each flight over any part of the defined object in correct time).

Explanation: if dimension of some object is over (for example) 50 m and is impossible or very difficult to observe from an aircraft, where the centre really is, some problems with evaluation maybe based and origin of disputes may be initiated.  

  • Hidden gates, constructed turn points and gates and turn points with influence for 30 or more % of overall score shall have radius at least 2 mm in the map.
  • For time gates must be set tolerances for covering of natural mistakes of the measurement method (accuracy of the GPS measuring equipments, rounding of tens and hundredths in latitudes and longitudes etc.), the minimal tolerance is ± 2 s for known gates and hidden gates at known track, ± 5s for gates at legs constructed during the flight.
  • In analyzing programme shall be set tolerances for covering of the natural mistakes of measurement method 10% in the radius (200 m radius will be set as 220 m radius).

Reason and explanation - GPS and FR records position of aircrafts are recorded in whole seconds. If  the first competitor will be in a gate 0,001 second before correct time (and is a good question, what is correct time after rounding for whole seconds), he will be penalized, because recorded will be previous second.  If the second competitor will be late 0,999 sec, he will be not penalized. This is not fair principle. Some mistakes of loggers must be taken into the mind. By my experiments, Amod´s logger mistake of position is round 10 – 15 m and two loggers in the same place in the same time had recorded some small differences – this is almost 1 sec. These mistakes must be covered by tolerance. Ground features

  • Photography’s, which shall be found and drawn in the competition map, should be made from an airplane from the heading of flight from distance at least 200 m. Deviation of the heading shall be less than 30° and vertical axes shall be sloping, not more than 45°. In tasks, where ground features should be discovered in specified space without specified track or heading of flight in this space, may be photographed from any position lying in the specified space. Photography’s shall be photographed in the same vegetation period as championship has to be flown. Natural look and colours mustn’t be changed. If in photography is more than one object, the relevant object must be highlighted by circle in contrast colour.  Correct photos may be in map as maximal 1 mm from the axis of the track and don’t be hidden behind trees, buildings or terrain obstacles from 200 m of height of flight at least last 250 m. False photography’s may be not nearly than 2 mm, from the axis of the track in the map.  The minimal dimension of the photography is 70 x 70 mm.
  • Markers, which shall be found and drawn in the competition map, will be made from strips of dimensions 4 m x 0, 8 m and shall be in contrast colour. Markers must be described in markers catalogue, using of markers – letters T, X,I,H and L is prohibited for prevention of changing with aviation signs. Markers shall be oriented in the heading of flight. Correct markers may be in map as maximal 1 mm from the axis of the track and don’t be hidden behind trees, buildings or terrain obstacles and must be visible from 200 m of height of flight at least last 250 m. False markers may be in the map not nearly, than 2 mm from the axis of the track.
  • Ground features mustn’t be located at least 1 km before and behind turn point and known gate, but using of turn point or gate photography is approved.
  • Interval between ground features is not limited. Balancing of the goals - Keeping of the track, keeping of the times (speed) and observing of the ground features shall have about 1/3 of the maximal achievable score of navigation task each.


Economy tasks Tasks with limited fuel shall be created with special care for safety. Areas for flying or specified tracks shall be designed with reference to possibility of emergency landing. If terrain isn’t safe for safety landing, request for sufficient amount of remaining fuel shall be applied in the task sheet. If amount of remaining fuel will exceed 2 kg, must be this requirement specified in the Local regulations or bulletin no later, than 60 days before start of championship. *(Notice and explanation – aeroplanes with fuel tanks in wings are usually equipped by a special tanks susceptible check of remaining fuel visually.  These additional tanks are usually from 5 to 10 litres. Application of requirement for 5 or more litres of remaining fuel requires a technical change in fuel system of an aircraft, which must be realised before the championship. In some countries exists rule, that flying without reserve of fuel for ½ hour of flight is prohibited. In like this case requirement for bigger amount of remaining fuel is necessary, but competitors shall receive this information in advance.)* Take off for economy task may be organized or by starting list or in the frame of opened flying window. Landing from the task with limited fuel shall be allowed in the specified space (whole airfield or specified runway or other marked space of dimension at least 300x25 m) Requirement for landing into the deck after task with limited fuel is possible only in the case, when more than one landing deck is available. If no deck will be free for landing, pilot may land everywhere in the airfield and no penalty for this landing will be applied. The deck isn’t free for landing, if any airplane, any equipment or any people are in the deck in the moment, when final approach is started.


Precision landings Landing deck should be located at the runway with or hard surface or short grass, 20 mm as maximum. Before the deck and behind the deck must be free space 100x25 m at least of the same quality of surface, as the deck is. Depending on altitude of the airfield length of the deck will be prolonged 1m for each finished hundred meters of altitude. If supposed temperature will be over 20°C, length of the deck will be prolonged 1m for each °C over the limit. The deck dimension will be the same for whole championship. (Comment and explanation – The minimal speed is defined for ISA conditions, this is air pressure 113,25 HPa in zero altitude and 15°C temperature. The air density diminishes depended on air pressure and temperature. The short deck in conditions of high altitude and/or high temperature is a big advantage for strong engines (R 912) and disadvantage for light two stroke engines- 20% penalty for takeoff deck) Threshold of the deck must be well visible from the aircraft during all final approach procedure. Short take off and short landing over the tape. Short take off and short landing tasks may be applied only, if the weather makes it possible to give the same chance to each competitor.  The tape must be in the same height for all competitors and must be straight. Deviations generated by wind don’t exceed 20 mm. Short landing and landing with measuring of remaining distance may be only organized in the domestic airfield of the championship. (Comment and explanation – short landing over a tape and very strong braking are types of tasks, where risks of small damages are higher. Destroyed or damaged tyre or wheel, broken brake pipe or brake string in some another airfield may make impossible to follow in the next task for example because isn’t possible to carry spare parts and needed tools in aircraft during competition flight.) The measuring of the wind during precision landing task must be assured at the deck. The precision landing tasks may be provided only if cross wind is 10 kt (5m/s) or less and tail wind don’t exceed 2 kt (1m/s). If wind exceeds these limits, task will be or interrupted or cancelled. If interruption is longer than 1 hour, will be task cancelled. If landing follows or  is a part of navigation or economy task, will be in the case of wind over limits installed into the landing deck marker X and pilots shall provide free landing everywhere in the airfield.



In last 6 championships (WMC 2005, EMC 2006, WMC 2007, EMC 2008, WMC 2009, and EMC 2010) weren’t navigation tasks strictly in accordance with the S10 A4 and no anyone new task sheet was approved by CIMA in advance. CIMA hasn’t some defined body and procedures for this work and this article is formal and was broken in each past championship. The better way is to ask organizers for publication of the task sheets in advance and set procedure of commenting these task sheets by CIMA monitor, competitors and team leaders before championship.

Some restrictions and limitations shall be established by S10 rule for task designers, because competitors mustn’t be object of experiments and at once shall have chance for training before competitions and the same rules shall be used in general for NAC.  Above are described some very basic rules and limitations.

Added by Robert HUGHES Last edited by José Luis Esteban on 15 Oct, 2010 09:53. Quick links: or 04 - CZE - Basic rules for tasks
Enter labels to add to this page:
Please wait 
Looking for a label? Just start typing.
Adaptavist Theme Builder Powered by Atlassian Confluence