Liferaft capacity

[Islander Jock]

I had an interesting question from a HUET trainee the other day who is a HSE boss for a major drilling company.

Is there a redundancy figure applied to the number of liferaft positions in helicopters operating over water vs the max number of POB? I know that just about all the common types like S76, Dauphin, Puma, Bell 212/412 have at least two rafts but where would it specify the what capacity each raft must have.

I've searched Australian CARs and CAOs but to no avail.

Would appreciate anyone who can steer me in the direction for authoritative reference.

Thanks in advance

[S76Heavy]

G reg s76.
max PoB 14.
2 liferafts for 10 persons each, each with a 50% overload capacity.
So you should be able to get all PoB into one liferaft.

[Islander Jock]

Thanks S76 Heavy,
That's sort of what I thought.

[Mars]

Islander Jock:

I’m not too familiar with Australian regulations but this is one area which the certification community makes an attempt at operational requirements. As the revision at the time of type certification governs the equipment basis for that aircraft (unlike operational regulations they are not retrospective), one has to search back in the archive to find the applicable standard for each type.

However, here is the latest certification code:FAR 29.801 Ditching

(a) If certification with ditching provisions is requested, the rotorcraft must meet the requirements of this paragraph and FAR 29.807(d), 29.1411 and 29.1415.

FAR 29.1415 Ditching equipment

(a) Emergency flotation and signaling [equipment required by any applicable operating rule must meet the requirements of this paragraph.]

(b) Each liferaft and each life preserver must be approved. In addition –

(1) Provide not less than two rafts, of an approximately equal rated capacity and buoyancy, to accommodate the occupants of the rotorcraft; and

(2) Each raft must have a trailing line, and must have a static line designed to hold the raft near the rotorcraft but to release it if the rotorcraft becomes totally submerged.

(c) Approved survival equipment must be attached to each liferaft.

(d) There must be an approved survival type emergency locator transmitter for use in one] liferaft.This is supplemented by the applicable guidance material:AC 29.1415. § 29.1415 (Amendment 29-30) DITCHING EQUIPMENT
…
(ii) Life rafts.

(A) Life rafts are rated during their approval to the number of people that can be carried under normal conditions and the number that can be accommodated in an overload condition. Only the normal rating may be used in relationship to the number of occupants permitted to fly in the rotorcraft.

(B) The life raft configuration (i.e., number of life rafts and capacity of each raft) presented for ditching certification must be adequate to accommodate all rotorcraft occupants using the overload rating of the remaining raft(s) after the loss of one raft of the largest rated capacity. Thus, at least two rafts are required for any transport category rotorcraft extended overwater operation.JAR-OPS 3 has an operational rule to ensure that the standard is appliedJAR-OPS 3.830 Life-rafts and survival ELTs for extended overwater flights
…
(1) In the case of a helicopter carrying less than 12 persons, a minimum of one liferaft with a rated capacity of not less than the maximum number of persons on board;

(2) In the case of a helicopter carrying more than 11 persons, a minimum of two liferafts sufficient together to accommodate all persons capable of being carried on board. Should one life-raft of the largest rated capacity be lost, the overload capacity of the remaining life-raft(s) shall be sufficient to accommodate all persons on the helicopter …When reading the operational text of JAR-OPS 3, it should be understood that the pilots have to be included in the number of persons on board.

You will see that your question is answered in the AC material and, for those who fly under JAR-OPS 3, the AC material and the operational rule.

[Islander Jock]

Thanks Mars,
More info than I need but at least now I have a better understanding of the methodology used to determine what capacity rafts are carried.

Cheers
IJ