Beginning in 1987, the European Commission sponsored
feasibility and definition studies for a tiltrotor transport, then known as
EuroFAR. It was hoped by Eurocopter that this ground work could be incorporated
in a forthcoming venture, announced in October 1998, for which other European
partners were sought. Eurocopter envisaged a 19/20 seat aircraft with an MTOW of
25,000kg and a service-entry date of around 2015. In early 1999 it undertook a
study, sponsored by the French defence ministry, into the military potential of
tiltrotors.
By 1999, 33 companies from nine European countries had joined
with Eurocopter to apply for EC funding, initially to build a test rig for a
proposed 10,000kg, 12/19-seat tiltrotor, provisionally known as Eurotilt.
Envisaged shares in the project, which could have led to a prototype, flying in
2004-05 and entry into service in 2008, included France 36%, Spain 25.7%,
Germany 22.3% and Italy 11.6%. Work-shares included Fiat Avio for transmission,
CASA for wings and Rolls-Royce Turbomeca for RTM 332 engines. Performance
parameters were 556km/h cruising speed over ranges between 370 and 1,480km and a
service ceiling of 7,620m. Development cost (1999) estimated as US$1.05 billion,
of which US$87.5 million for ground test rig.
Meanwhile, in July 1999, Agusta announced the 10-tonne, 20-seat
Erica Tiltrotor and was seeking ˆ90 million of funding from EU's 5th Framework
research programme to build a ground test vehicle (GTV). Testing was envisaged
five years after GTV go-ahead; prototype first flight in further two years.
Backing received from 16 companies, including GKN Westland (UK), ZF
Luftfahrttechnik (Germany), IAI (Israel), Aermacchi (Italy), NLR (Netherlands),
Gamesa (Spain) and Saab (Sweden).
Erica was second-generation tiltrotor, incorporating
improvements over BA609 and V-22. Engines mounted inboard, underwing, driving
connecting shafts to proprotors at wingtips. Outboard half of wing was to tilt
with proprotors, obviating blocking effect of fixed wing and increasing vertical
lift by 12%. This improvement would permit smaller proprotor diameter,
increasing cruising speed and allowing almost conventional rolling landings,
with outboard wing tilted by only 5 to 7° to prevent ground contact.
In October 1999, European Commission rejected separate funding
of competing European tiltrotors and urged merger of Erica with Eurotilt.
Common research project, known as 2Gether (second-generafion
European tilting highly efficient rotorcraft), submitted to European Commission
on 31 March 2000 by Eurocopter, Westland and Agusta (since merged as
AgustaWestland). Timetable envisaged initial ˆ95 million study between 2000 and
2004, followed by demonstrator first flight in 2005 (additional ˆ250 million)
and production programme (ˆ1,000 million) leading to series manufacture
beginning in 2010. Launch version would have had 10-tonne MTOW and carried 20
passengers.
European Commission rejected 2Gether as too costly and
insufficiently innovative. New development proposal submitted in March 2001;
cost ˆ40 million to ˆ60 million, with industry providing half; features tilting
outer wing, as proposed by Agusta; early research devoted to overcoming
additional technical difficulties of this configuration; flight demonstration
could begin in 2007-08. Study team also to include Mecaer and Teleavio of Italy;
Gamesa and Sener of Spain; UK's FHL; ZF of Germany; ONERA, DLR, NLR and CIRA
research institutes; Israel Aircraft Industries; and Pratt & Whitney Canada.
These joined by Flight Science and Technology Laboratory at Liverpool
University, UK, which inaugurated in June 2001 a flight simulator to be used in
developing a control system for Eurocopter's Eurotilt submission.
Various research efforts merged into RHILP (Rotorcraft Handling
qualities, Interaction and Load Prediction) project, combining Eurocopter (in
France) and Eurocopter Deutschland, plus research organisations CIRA (Italy),
DLR (Germany). NLR (Netherlands), ONERA (France) and University of Liverpool
(UK). Evaluation and risk-minimisation project began March 2000 and so far
embraces four work packages: WP1 for handling qualities definition, employing
moving base simulator at Liverpool (first four with Bell XV-15 parameters, but
progressing to Eurotilt in August 2002); WP2 analysing specific flight phenomena
using 1:7 scale model at Eurocopter, Marignane; WP3 for loads alleviation; and
WP4 use of Marignane's SPHERE simulator for piloted simulation tests. Completion
due in 2003, although RHILP is only one of several Critical Technology Projects
envisaged up to 2005 and its results will be incorporated in HOST flight
mechanics software configured to represent Eurotilt
Jane's All the World's Aircraft, 2004-2005