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Robinson R66
a preview by Philip Greenspun, ATP, CFI-H; updated March 2009
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The Robinson R66 is a five-seat turbine-powered helicopter with a
two-blade teetering rotor system. It should be certified by the end
of 2009, with customer deliveries in 2010.
The Robinson R66 offers two comfortable front seats separated by a
central cyclic control, the famous Robinson "T-bar" design. The back
seat is just barely wide enough for three passengers and has enough
legroom for a passenger up to perhaps 5'4" in height. The airbag
seatbelts that have been standard since 2005 on general aviation
aircraft from Cessna, Cirrus, Diamond, and Piper are not offered on
the R66. The machine offers cargo space underneath the seats and in a
spacious rear cargo compartment.
Engine controls are mechanical, with no FADEC to prevent hot starts,
hung starts, or overtorquing, any of which can be caused by a student,
low-time, or distracted pilot and all of which can easily cost $50,000
to inspect and repair. Flight instruments are mechanical, the
traditional 6-pack of steam gauges. No autopilot is available.
This article is based on the author's February 2009 visit to the
Robinson factory and inspection of a flying R66.
History
Bell Helicopter at one time made more helicopters than any other company
in the world, primarily on the strength of the B206 JetRanger. Frank
Robinson introduced the two-seat R22
in the late 1970s and it was noteworthy for being very fast while
offering the lowest operating costs of any helicopter. Bell said " We
don't have to worry about this cutting into JetRanger sales; he will
never make a four- or five-seat helicopter." Frank Robinson introduced
the four-seat R44 in the early 1990s.
The R44 came very close to a lot of JetRanger numbers in terms of
payload and cruise speed, at an acquisition cost of one quarter that of
the JetRanger and an operating cost of less than half. By limiting the
power drawn from the piston engine, the power plant/tranmission
reliability of the R44 has been very close to that of small
turbine-powered helicopters.
Faced with a decline in JetRanger sales due to the R44, Bell said "We
don't have to worry because there are some customers who demand a jet
engine and there are some customers who need five total seats. Robinson
will never make a jet-powered or five-seat helicopter."
In March 2007, Frank Robinson announced the Robinson R66, a jet-powered
five-seat helicopter. In January 2008, Bell Helicopter announced that
it was ceasing production of the JetRanger.
Safety
The Robinson R66 is unlikely to be inherently safer or offer more
powerplant/transmission reliability than the R44. Turbine engines have
a reputation for extreme reliability, but physically small turbines,
such as those that go into low-power helicopter engines, are subject to
a lot of thermal stress and are not nearly as reliable as the turbines
in an Airbus. Piston engines have a reputation for unreliability, but
that was earned when the engines were operated at 100 percent power.
The R44 is a demonstration of the most reliability that you could ever
get from a piston engine; the Robinson R66 and similar light turbine
helicopters demonstrate the least reliability that you could ever get
from a turbine engine, especially when you factor in the need for a very
sophisticated transmission (turbines spin at up to 50,000 RPM;
helicopter rotors spin at around 400 RPM).
Compared to the R44
The Robinson R66 bears a strong physical resemblance to the R44.
Instead of a cooling fan in the back, there is a small turbine engine
and a big exhaust pipe. The space formerly occupied by the piston
engine is now a baggage compartment, big enough for a few full-size
suitcases and accessed via a single door on the passenger side. The
R44 has reasonable baggage capacity underneath the four seats, but no
compartment is large enough for a set of golf clubs, for example. The
back seat of the R66 has the same amount of legroom as an R44 (i.e.,
not much), but is slightly wider and therefore can theoretically seat
three people.
The Robinson R66 should be more profitable for medium-volume
sightseeing operations, assuming that the rides are short and
passengers can tolerate being crammed into the back seat. Customers
tend to arrive in groups of two, so having four passenger seats rather
than three will be a help.
Many foreign militaries use the R44 as a primary trainer. The U.S. Army
uses the JetRanger because (1) taxpayer money is free, and (2) they want
army pilots to have turbine startup and shutdown experience from Day 1.
The R66 probably won't win over the U.S. Army, but it should be hugely
popular with foreign armies.
Compared to a Eurocopter EC120
The Eurocopter
EC120 is a lovely five-seat machine with a fenestron (shrouded)
anti-torque rotor in the tail. A 10-year-old EC120 sells for about
$900,000. Due to the conventional tail rotor and less paranoia about
waking up the neighbors, the Robinson R66 will be substantially
noisier than the EC120, whose flyover noise is 3 dB quieter than the
R44 (FAA
Advisory Circular AC36-1H). It will also have more tail rotor
authority.
The EC120 has a smooth three-blade rotor system that is always going
to be more comfortable at higher airspeeds than a two-blade Robinson
or Jet Ranger rotor. The EC120 has fancy glass engine parameter
displays, but no FADEC. An experienced EC120 pilot had this to say
"The EC120's start up is all pilot-controlled. The EC120 is very easy
to hot start, as one needs to manipulate the throttle somewhat and the
thumb is holding the start/cranker in position, so it is tough to fine
tune the throttle at the same time."
The EC120 has a variety of glass cockpit and autopilot options;
Robinson is going to deliver the R66 with a 1950-style six-pack of
steam gauges.
The EC120, like other traditional turbine helicopters, has a very
large and comfortable back seat, making it a credible machine for
executive transport. The EC120 is a vastly better ship for photo
enthusiasts, with a large sliding photo window in front and a rear
door that slides completely open or closed in flight. With a Robinson
R66 you would need to do any photo mission with a door removed
entirely, not very practical in cold climates.
The Robinson R66 should be substantially cheaper to buy and operate
than a new EC120. Eurocopter has developed a bad reputation for
service and support. After any initial teething problems are
resolved, the R66 should spend more of its time in the air and less in
the maintenance hangar waiting for service bulletins and airworthiness
directives to be performed.
In a December 2007 survey by Rotor and Wing, Robinson
earned the #1 spot for customer satisfaction. Eurocopter was near the
bottom.
Compared to an old JetRanger
A new Robinson R66 is likely to sell for the same price as a
10-year-old Bell 206
JetRanger, which first flew in 1962. The aircraft are powered by
very similar engines, from the same original
Allison design, and should perform similarly. Maintenance,
overhaul, and spare parts costs for the JetRanger should be
substantially higher, particularly if Bell elects to raise parts
prices on the 206 in order to encourage customers to buy its newer 407
design. This is what happened with the Bell 47, the old piston-engine
M*A*S*H helicopter. Spare parts got so expensive that it became
cheaper for customers to operate the jet-powered 206.
The Jet Ranger and Long Ranger helicopters have much bigger and more
comfortable back seats than the Robinson R66. The Bell helicopters
also have useful sliding photo windows.
Before the Crash of 2008, an airworthy 1970s JetRanger could be
purchased for $250,000, with a pristine example going for closer to
$500,000. The most popular civilian helicopter ever made, with over
7,000 manufacturered, the huge fleet of used B206s available is the
strongest competition to any new five-seat jet-powered helicopter.
Compared to the Sikorsky S-434
In late 2007, Schweizer, a subsidiary of Sikorsky, announced a
derivative of their three-seat Schweizer 333 helicopter. The new
machine, dubbed 434, has a four-blade rotor system derived from a
remotely piloted military helicopter. This could be a very nimble
helicopter to fly and has already been sold to Saudi Arabia for use in
military training. Seating is provided for three people in a training
configuration or four in "utility". Without a fifth seat or a cargo
compartment, it is tough to see how the S-434 will compete with the
Robinson R66. Given how fat Sikorsky gets on its military contracts,
it is tough to imagine them investing the effort to develop a
competitor to Robinson's personal helicopter line.
At Heli-Expo 2009, Sikorsky announced that the S-434 had first flown
on December 18, 2008. Certification is expected in 2010 with customer
deliveries in 2011. The price is approximately $1 million.
PowerPlant
Back in 2007, Robinson and Rolls-Royce announced that the R66 would
use the RR300, a modern somewhat simplified derivative of the Allison
engine that has powered thousands of JetRangers. Rolls-Royce says
that Full Authority Digital Engine Control (FADEC) will be a
customer-specified option. Frank Robinson never met a computer chip
that he thought could do a better job than a nervous 20-hour student
pilot, so my guess was that the R66 will ship with a manual engine
control system, just like a 1962 JetRanger. As a practical matter,
that means hot starts ($50,000+) and in-flight distractions resulting
in overtorquing and overtemping. Considering how many students
overspeed the R22 and R44 in training, and the expense of inspecting
an abused turbine engine, the lack of a FADEC would preclude the R66
as a civilian primary trainer. My suspicion was confirmed in February
2009 when Frank delivered a talk at Heli-Expo saying that the R66
would have old-school mechanical engine controls.
The RR300 in the R66 will supposedly be rated at 300 hp for takeoff,
240 hp max continuous, and 220 hp in cruise flight. This compares to
420 hp takeoff power in a modern JetRanger. This compares to 245hp
takeoff and 205hp max continuous in the R44 Raven II.
When
Robinson has not officially announced a date for R66 certification or
deliveries. Various news reports have speculated that helicopters
will start coming off the line in 2010. The R66 was seen flying
around Torrance, California starting in 2007. Folks at the factory in
February 2009 were hoping that the machine would be certified in 2009.
Wishlist
In case Frank Robinson happens to read this page...
- FADEC to prevent student or low-time pilot damaging engine
- lightweight glass cockpit for instrument training, presenting
synthetic terrain for maximum safety in the event of inadvertent IMC
encounter
- (facilitated by the foregoing) three lines of computer code to look
at airspeed and vertical speed and, if one is sinking faster than 300
fpm and going slower than 30 knots, synthesize a voice saying "settling"
into the intercom
- (sunburn and heatstroke prevention) LCD or electrochromic material
inside the bubble Plexi that can be electrically dimmed (and that
returns to clear if power is removed) or at least a coating such as 3M
Solar Reflecting Film that blocks IR (heat) and UV (sunburn/heat)
— since around 2000 a Toyota Camry or Honda Accord has come with
coatings like this
- fuel totalizer and single fuel gauge summing the results of the
sensors in the two tanks
- conventional two-cyclic control system so that passengers are less
likely to knock the cyclic and so that grizzled old military guys won't
complain about the T-bar
Conclusion
The R44 is a great two-person helicopter, with the cramped rear seats
treated as a cargo shelf. With only two people on board, the machine
has a huge amount of reserve power from its simple piston engine. The
R44's lack of rear-seat legroom precludes its use as an executive
transport. The proximity of the cyclic to a front-seat passenger
makes the R44 a little worrisome for short sightseeing tours where
there is not a lot of time to brief passengers on the importance of
not knocking the control. For most customers, therefore, the R44 ends
up being flown most of the time with only one or two people in its
four seats.
What do you get by stepping up to the R66? The same lack of rear-seat
legroom. The same T-bar cyclic right next to a front-seat passenger.
Additional cargo space for bulky items. Is it a true five-seater?
Absolutely... if all of your friends are 5'4" tall. Otherwise, it is
a two-seat helicopter with a cargo shelf, same as the R44.
The R66 will be substantially more useful than the R44 in some foreign
countries or on oil platforms where Avgas is difficult to obtain
(though note that the R44 Raven I can run on super unleaded car gas).
The R66 may be useful to oil rig operators who want an inexpensive
Jet-A-fueled machine for ferrying out packages and parts, a job
currently performed by ancient JetRangers.
For executive transport or sightseeing operators, the R66 would have
to be priced substantially cheaper than a used EC120 in order to be
attractive.
More
Text and photos Copyright 2008-9 Philip
Greenspun.
philg@mit.edu
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