SAN LUIS OBISPO – While watching planes at your local airport, you’ll notice that at their core, almost all of the planes look very similar, whether at a general aviation airport, a large international airport, or even a military base.
Aerospace engineers design aircraft like this for various reasons: ease in manufacturing, existing resources, and a general commonality between different models. However, this doesn’t necessarily represent the best possible design.
Very few aircraft manufacturers are willing to depart from the norm. However, legendary aircraft designer Burt Rutan has devoted his entire life to such designs, creating some of the most odd-looking aircraft in the sky.
One of the Smartest Aircraft Designers
After graduating from California Polytechnic State University in San Luis Obispo, CA with a degree in Aerospace Engineering, he went to work as a flight test engineer at Edwards AFB and then went to Bede Aircraft in Wichita, KS to be the Director of Development for the kit-built aircraft, the BD-5.
A variant of that aircraft, the BD-5J, still holds the record as being the smallest jet aircraft to ever be produced. In 1974, Burt left Wichita and moved to Mojave, CA to found the Rutan Aircraft Factory.
The first aircraft that he created was the VariViggen. This delta wing, pusher style aircraft became the foundation for the VariEze and Long-EZ. These both became some of the most famous kit airplanes ever produced, and have even spawned new designs based on their configuration.
Rutan also worked with NASA to created the AD-1, an aircraft with a pivoting oblique wing to decrease drag. It utilized two of the engines that were used on the BD-5J, which Rutan worked on in the past. In 1982, Rutan founded Scaled Composites to further his love for pushing the boundaries of aircraft design.
Rutan Model 202 Boomerang
Rutan devoted the Rutan Aircraft Company to selling and maintaining the homebuilt aircraft, so he founded Scaled Composites in 1982. Most of his later (and externally sponsored) designs were built through them, but some that were more personal, he kept and built under the Rutan name. The most notable of these aircraft is the Rutan Model 202 Boomerang, which was built in 1996.
The Boomerang is a twin-engine, pressurized, five seat general aviation aircraft. However, it is a distinctly asymmetric aircraft, with one engine on the nose of the aircraft, and one on the left wing, attached to a secondary boom.
The horizontal stabilizer extends to the right of the fuselage, between the fuselage and the secondary boom, but not to the left side of the secondary boom. Additionally, the wing is swept forward, like only a handful of aircraft ever produced.
The Engineering Behind the Boomerang
All these changes to the aircraft are not for show. Burt Rutan wanted to design a twin-engine aircraft that would minimize the effect of asymmetrical thrust in the event that the aircraft loses an engine, and allow the aircraft to maintain directional control in an easier way. Rutan based the design on one of the most famous aircraft in the class, the Beechcraft Baron 58.
The right engine was moved forward to the nose to reduce drag, weight, and complexity from the system. The left engine had to be moved backwards to compensate. The engines are the same model, but are rated at slightly different power increments to perfect the design, but are both smaller than that on the Baron.
The wing was swept forward to reduce the effect of the left engine with the rest of the aircraft and was moved to the left as well to account for the change in engine position. The secondary boom was added to decrease flutter at the tail, which was also reduced due to the new controllability metrics of the aircraft and its lighter weight (from both the new design and the use of carbon fiber).
All of these changes revolutionize the way that the aircraft flies. If an engine were to fail, it would only need minimal rudder input to maintain control. The center of gravity falls between the fuselage and the secondary boom, and is further ahead than a traditional forward limit. This will actually never allow the aircraft to really stall, preventing any issues of when an engine becomes inoperative while inflight.
The stall speed of the aircraft at maximum takeoff weight is 88 kts, but the minimum control speed is 80 kts. Although the Boomerang uses less powerful engines, it actually has much better performance characteristics. The Baron cruises at 180 kts. while the Boomerang cruises at 220 kts. The Boomerang’s maximum range is around 2,100 nm. Under the same conditions, the Baron’s is only around 1,100 nm. The wing’s aspect ratio is almost double as well.
SkyTaxi’s MB-300 Boomerang
In 1997, Joe and Neil Morrow founded SkyTaxi, with the intent on creating an on-demand flights at the same price as commercial. The commissioned Rutan to build them a prototype aircraft called the MB-300 Boomerang with the intent for it to be certified. Using the Boomerang would allow the company to operate flights at a much cheaper rate than with any other aircraft. They began flights with a Cessna 414 in 1998.
The Morrows and Rutan worked together for four years, but they abandoned the project in 2002 to focus on their Cessna operations. Rutan partially finished the prototype of the MB-300, so once everything was complete, only one Boomerang was finished (N24BT). Rutan used N24BT as his personal aircraft, but was left in a hangar until 2011 when it was restored to flying condition once again.
He took the plane to AirVenture 2011 in Oshkosh, where he announced that it would soon go to a museum. However, he fortunately changed his mind, and gave the aircraft to Scaled Composites engineer Tres Clement. He keeps the aircraft in flying condition, all while based at San Luis Obispo Airport (SBP), serving the college town of Rutan.
On-Board the Boomerang
In November 2019, Airways had the distinct privilege of flying on the Rutan Boomerang. Prior to takeoff, all passengers had to sign a waiver stating that they understood the risks of flying on-board an experimental aircraft. Each passenger was briefed on their responsibilities as well.
Tres Clements would be the pilot in command with world-record breaking aircraft designer and aerospace engineering professor, Paulo Iscold as the second in command. Airways would be in the back cabin with aerospace engineer, David Sanchez. Our job would be to open the door in case of emergency and to work on the landing gear if it gave problems.
Paulo would give speed callouts and help retract the landing gear. Although there are only four seats on the aircraft, there are two radically different doors to enter and exit, both on the right side of the fuselage. Those sitting in the back of the aircraft have a conventional door to enter and exit from. The two people in the front seat climb through the front windshield.
Oddly enough, the pilot in command sits on the right side, so Paulo had to climb into the aircraft and step into the adjoining seat, similar to some other general aviation aircraft. David sat in the forward-facing rear seat with Airways in the rear-facing seat.
After a long and arduous taxi (because of no real center nose gear), we departed runway 29 at SBP as “Experimental 24BT” and climbed north towards the seaside community of Morro Bay. Once over uninhabited land, Tres began to show off some of the capabilities of the aircraft.
Each engine’s power was reduced to idle one at a time to demonstrate the controllability of the aircraft. When simulating only one operable engine, the aircraft performed extremely well. Although the aircraft was technically stalled, it was still generating lift and was easily controllable.
It’s handling qualities were also second to none, with both Tres and Paulo at the controls. It handled very similar to a single engine aircraft, and its performance came close to a turboprop, very different from anything else that is currently flying. After an unforgettable 37 minutes of flying time, we returned to runway 29 at SBP and taxiied back to the hangar.
The legacy of the Boomerang and Burt Rutan will truly live on forever in the aviation community. Recently, toy vehicle manufacturer Matchbox approached Burt Rutan to make a die-cast model of the Boomerang, but with a generic paint scheme, like so many Matchbox aircraft.
However, Burt insisted that it remain in its authentic scheme. Although only one Boomerang was completed, it will truly serve as a reminder of how robust an aircraft design can be—pushing the boundaries of normality to achieve a unique solution.
All images: Author