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Canadian Defence Procurement — updated and revised January 2004
Politics, Procurement Practices, and Procrastination:
the Quarter-Century Sea King Helicopter
Replacement Saga
Part 6 — Open for Business:
the Contenders for the ‘NSA’ (Continued)
The third contender for DND’s ‘New Shipboard Aircraft Project’ was the entirely new EH-101. This
helicopter was larger than the other candidates – indeed, the EH-101 was larger than the Sea King
itself. The EH-101 also had 3 turbine engines making it more powerful
than the other contenders.
The EH-101 was jointly developed by Agusta (who built Sea Kings under licence in Italy) and Westland
(who licence-built Sea Kings in Britain). EH Industries was formed in 1980 to market this multipurpose,
medium-lift civilian/military helicopter.
Although partly designed to replace Sea Kings, the maritime version of the EH-101 owed little to that
earlier helicopter from a design point of view. The rotor diameters and cabin size of both Sea
King and EH- 101 were roughly the same but, there the similarities ended. Unlike the Sea Kings, the
new EH-101 didn’t even pretend to be amphibious [1] and its rotor blade design was based on those of
Westland’s Lynx.
The use of three engines is not unique (both Sikorsky and Aérospatiale fielded triple-engined
helicopters earlier) but the arrangement EH Industries chose was unusual. The third engine was positioned
behind the rotor mast (as Sikorsky had done with the CH-53E) but, in the EH-101, the other engines are splayed
outward forming what has been described as an ‘arrowhead’ arrangement. One significant difference from
the Sea King and two other NSA contenders is the EH-101’s use of lateral air intakes which are
said to reduce icing problems for those engines.
[1] Despite their ‘flying boat’ hull and sponsons, Sea Kings still rely on flotation bags
should they be forced to make a water landing. EH Industries, Aérospatiale, and Sikorsky all now rely on
flotation bags alone to gain improved aerodynamics.
< Part 5 — Open for Business:
the Contenders for the ‘NSA’ Requirement
> Part 7 — Narrowing the NSA Field and Racing
for the Finishing Line
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