scope:

(a) The mandatory requirements set out in this Standard are those basic requirements needed for the design and development of airworthy RPAS for all three UK Armed Services based on the requirements set out in the following references:

NATO STANAG 4671 Unmanned Aerial Vehicles System Airworthiness Requirements (USAR) Edition 2;

NATO STANAG 4702 Rotary Wing Unmanned Aerial Systems Airworthiness Requirements;

NATO STANAG 4703 Light Unmanned Aircraft Systems Airworthiness Requirements;

NATO STANAG 4746 Unmanned Aerial Vehicle System Airworthiness Requirements for Light Vertical Take-Off and Landing Aircraft (To be published);

(b) Supplemented by the following UK national reservations.

NB the terms RPAS, RPAV as used in Def. Stan 00-970 and UAS, UA as used in the NATO STANAG are interchangeable.

(c) UK national reservations STANAG 4671:

Amend USAR paragraph U50. Insert new paragraph U50(c) Demonstrate that there is adequate margin (e.g. 15%, to be agreed with the Certifying Authority) between V_s and V_{min FCS} (i.e. to take account of gust) and that V_{min FCS} is robust.

Insert after USAR paragraph 201(ii). iii) V_minDEMO to be equivalent to V_minFCS

Amend USAR paragraph AMC.1309(b). Insert the additional sentence at (5)(c)(i). more severe criteria may be needed for large aircraft; Insert the additional sub-paragraphs after (5)(c)(1).

(i) For large aircraft from 5,700kg up to 20,000kg MTOW (with the exception of propeller-driven twin-engine RPAS, refer paragraph ii). At RPAV system level, the combination of all Catastrophic failure conditions is characterised by an occurrence of 10^-6 per flying hour or less (with the calculation method subject to Certifying Authority agreement).

(ii) For propeller-driven twin-engine RPAS from 8,618kg up to 20,000kg MTOW, at RPAV system level, the combination of all Catastrophic failure conditions is characterised by an occurrence of 10^-6 per flying hour or less (with the calculation method subject to Certifying Authority agreement).

(d) UK national reservations STANAG 4702:

With respect to (WRT) paragraph 631 Bird Strike: The energy requirement derived from CS-29 associated with a 1 kg bird is considered disproportionate for a sub-3175kg rotorcraft. Therefore requirement UK.631a has been created.

WRT paragraph 833: CS 27.833 (& CS29.833) specifically relates to Combustion heaters, as defined in SAE Aeronautical Standard AS143B, which must be approved in accordance with TSO-C20. TSOs do not exist for other heater types. See FAR AC 29-2C. A combustion heater requirement is considered unnecessary for this RPAS standard however if such a system is deemed necessary for a specific RPAS this could be added as a Special Condition. Requirement 833 has therefore been marked as N/A (Consistent with requirement 859).

WRT paragraph 1353: Sub-paragraphs (f) and (g) are specifically applicable to Nickel-Cadmium batteries, but may also be relevant to other battery technologies. Civil Certification Specifications do not apply these rules to Lead Acid batteries. Applicability of Subparts (f) and (g) to new technology batteries/charge devices (for example Lithium-Ion and super-caps) should be considered by the applicant and incorporated into the Type Certification Basis through application of Special Conditions.

Re-instate 'Nickel-Cadmium' to USAR RW.1353 (f) and (g)

(f) Each nickel cadmium battery…..

(g) Nickel cadmium battery installations….

WRT paragraph U1607: the requirement does not require growth potential for the DATA link.

The following paragraph is to be added to the requirement:

(f) The capacity of the data link must be determined to provide an acceptable margin under the highest usage condition expected throughout the Service life of the platform.