Wolfgang lintl, Germany
07 clarification in case of oil injection 2 stroke engines
5.4.1 The maximum amount of fuel, which may be carried for records, is stated in S10 Chapter 3. Fuel shall be measured by mass, or volume. For Championships, the maximum amount of fuel permitted for limited fuel consumption tasks is 15 kg for aircraft flown solo and 22 kg for aircraft flown with two people, or the equivalent in litres, although lesser amounts may be stated at briefing.
5.4.2 The permitted amount of fuel shall be put into the aircraft tank when it is empty.
5.4.3 An official observer must control fuelling. In championships this may also be done by a competitor or team leader from a rival team.
5.4.4 An official observer must seal the tank. In championships, sealing of tanks is optional if aircraft are moved under supervision of officials directly to the take off place.New text
In some rare cases, competitors uses two stroke engines working with oil injection. Current regulation are not clear, how to measure the given amount of fuel.