Text in force at CS29-12: from CS29-0, effective 14 Nov 2003.
For each airspeed indicating system , the following apply:
(a) Each airspeed indicating i nstrument m ust be calib rated to in dicate true airspeed (at sea-level with a standard at mosphere) wi th a m inimum practicable in strument calib ration erro r when the corresponding pitot and static pressures are applied.
(b) Each system must be calibrated to determine system erro r excluding airspeed instrument error. This calibration m ust be determined:
(1) In l evel fl ight at speeds of 37 km/h (20 knots) and great er, and over an appropriate range of speeds for fl ight condi tions of cl imb and autorotation; and
(2) During take-off, with repeatable and readable indications that ensure:
(i) Consistent realisatio n o f the field len gths sp ecified in th e Rotorcraft Flight Manual; and
(ii) Avoidance of the critical areas of t he hei ght-velocity envel ope as established under CS 29.87.
(c) For Category A rotorcraft:
(1) The i ndication m ust allow consistent defi nition of t he take-off decision point; and
(2) The system error, excluding the airspeed instrum ent calibration error, m ay not exceed –
(i) 3% or 9.3 km /h (5 knots), whichever is greater, in lev el flig ht at speeds above 80% of t ake-off safety speed; and
(ii) 19 km/h (10 knots) in climb at speeds from 19 km /h (10 knots) below take-off safety speed t o 19 km /h (10 knots) above VY.
(d) For Category B rotorcraft, the system error, excluding the airspeed instrument calibration error, m ay not exceed 3% or 9.3 km /h (5 knot s), whi chever i s great er, in level flight at speeds above 80% of t he cl imbout speed at tained at 15 m (50 ft) when complying with CS 29.63.
(e) Each system must be arranged, so far as practicable, to prevent malfunction or serious error due to the ent ry of m oisture, di rt, or ot her substances.
(f) Each system must have a heated pitot tube or an equi valent means of prevent ing malfunction due to icing.
ED Decision 2003/016/RM · Source