Webster

The Constitution was made to guard the people against the dangers of good intentions." --American Statesman Daniel Webster (1782-1852)


Friday, October 19, 2018

Unusual Airplane...The Rutan Boomerang


I saw this weird airplane on a facebook post and I decided to "Google" it and it was legit, it is an actual airplane and it flies and has some impressive specs especially for a "General Aviation" airplane.   I pulled the specs from the Company website.






Design


“The Boomerang is a new high performance pressurized 5 place light twin intended for personal transportation. Its basic goals were to provide optimum performance from two turbocharged 200 hp Lycoming reciprocating powerplants. Probably one of the most difficult tasks faced in the development of this aircraft was explaining why I would design a configuration that is asymmetric.  In fact, an early comment as the aircraft arrived at the Experimental Aircraft Association International Air Show at Oshkosh, Wisconsin this year, was from a fellow who ran up and remarked, “What in the hell were you smokin’ when you laid that one out?”  
– Burt Rutan (1996)
In trying to explain how Burt Rutan developed the idea of the Boomerang, he used a step-by-step comparison of a “traditional” twin-engine aircraft (Beech Baron BE58) and his design.
Step-by-Step Comparison : Baron vs. Boomerang
Boomerang and Baron design comparison
Baseline Baron 58P
Span = 37.8 ft. Wing area = 188 sq.ft. Stab area = 56 sq.ft
Vert Area = 24.4 sq.ft. Total BHP = 650 Empty Weight = 4018 lb
Useful Load = 2222 lb Max Fuel = 1140 lb Gross Weight = 6240 lb
Stall = 78 kt Cruise (75% 20kft) = 224 kt Range (75% 20kft) = 975 nm

Boomerang and Baron design comparison
Left engine moved outboard to improve symmetry at low speeds and to reduce cabin noise.
 Boomerang and Baron design comparison
Both engines moved inboard to reduce MCS. Right engine moved forward to clear fuselage. Left engine moved aft to balance.
Boomerang and Baron design comparison
Wing skewed to support engines and to reduce left engine interference.
Boomerang and Baron design comparison
Composite construction allows smaller, higher aspect ratio wing. but configuration is now nose-heavy, thus left wing is swept forward. This helps, but configuration is still nose-heavy.
Boomerang and Baron design comparison
The weight savings allows smaller engines and tail area can be reduced.
Boomerang and Baron design comparison
Higher aspect ratio tail flutter problem is fixed with nacelle boom. This allows additional baggage room in boom.
Boomerang and Baron design comparison
Right engine is moved to the fuselage to reduce weight, cost and drag. Lateral balance is restored by moving entire wing to the left. MCS is now well below stall.
Boomerang and Baron design comparison
Left engine is moved outboard to reduce cabin noise and to eliminate prop interference. Entire wing is moved left to restore lateral balance.
Boomerang and Baron design comparison
Twin small vertical tails improve low speed handling, reduce weight and allow low-drag pressure-recovery aft fuselage.
Boomerang and Baron design comparisonContinue evolution
  • Round fuselage, increased room.
  • Laminar flow flying surfaces.
  • Higher wing loading.
  • Aspect Ratio to 13.2.
  • Full-span camber control for aileron/flap/wing optimization
Boomerang and Baron design comparisonBoomerang and Baron design comparison
Baron 58P Boomerang
3.8psi cabin 4.6psi cabin
6 seats 5 seats or 4 seats+1 bed
3% more span 15% wider cabin
84% more wing area 20% longer cabin
65% more tail area 92% more aspect ratio
59% more engine power 10% higher stall speed
62% more empty weight 45% more climb rate
13% more fuel 41 kt higher cruise speed
45% more gross weight 56% more range at 75%

92% more max range

Immune from MCS accidents





Technical Specifications

This table summarizes the performance and technical specifications of the Boomerang:
Engines Lycoming TIO-360A1B (200 hp) RHS Lycoming TIO-360C1A6D (210 hp) LHS
Seating 5 (includes pilot)
Empty Weight 2370 Lbs
Max Fuel 1026 Lbs
Max Cabin Payload 1000 lb
Payload at Max Fuel 865 lb
Max Gross Weight 4242 lb
Wing Span 36.7 ft
Wing Area 101.7 ft²
Length 30.6 ft
Aspect Ratio 13.2
Vmax 283 knots true (326 mph) at 18,000 ft
Max Cruise At 22,000 ft and 75% power:  264 kts/304 mph at 1500 nm range
Economy Cruise At 24,000 ft and 50% power:  210 knots/242 mph at 2100 nm range (Range includes Takeoff, Climb and 45 min reserve)
Max Climb 1900 fpm (2900 fpm at 2800 lb)
Stall Speed 88 knots (at 4200 lb) or 73 knots (at 2800 lb)
Pressurization To 7000 ft at 22,000 ft altitude
Gear Electric retract
Miscellaneous Full-span aileron reflex

Boomerang specs
Download PDF 

The Cockpit is totally computerized with LCD screens allowing for multiple selection of functions from pneumatic, hydraulic, fuel management,engine management  passenger comfort and many other selections plus required analog gauges.

To see more, check HERE  

2 comments:

  1. I wonder if he was inspired by the Bv 141 ( and yes, it flew ! )
    https://www.tandymedia.com/wp-content/uploads/2016/05/APN1512.jpg

    ReplyDelete
    Replies
    1. Hey Jerseygirlangie;

      I thought I had seen all the weird planes that the 3rd Reich had designed, but that one is a new one. I will start digging into it and thank you for the link:)

      Delete

I had to change the comment format on this blog due to spammers, I will open it back up again in a bit.