BuzzBomb 400 Kit Review

Stevens Aero Buzz Bomb now complete, ready for first flight

Stevens Aero Buzz Bomb ready for first flight

I recently completed the Stevens Aero BuzzBomb 400 radio control model airplane kit and flew a successful test flight. I am very pleased with the results.  Following is a recap of my kit build and initial flight experience.

The BuzzBomb 400 is a recreation of a classic 1940s free flight design of the Buzzard Bombshell model plane. In those early days of model flight the superstars were all free flight aircraft as radio control hardware was just starting to be invented.

The free flight aircraft of that era needed to be well designed as they had to fly right the first time launched, without the chance to assist with a control input from the ground. In addition these early aircraft were quite large to accommodate the heavy gas engines of the time.

The Buzzard Bombshell met all of these requirements and was a successful design. Thus, it makes good sense to adapt the inherent flying qualities of this aircraft to a modern day slow flying radio control model.

Stevens Aero did a great job with this aspect of their BuzzBomb 400. The top mounted wing has generous area as well as tip polyhedral that allows for stable flight with three channels of control (rudder, elevator and throttle).  The fuselage is roomy enough for any type of radio system.  The tail control surfaces are more than adequate for the relaxed sport flying that is the forte of this type of design.

Like all other Stevens Aero kits, the balsa wood is of top quality. The laser cutting is flawless.  The included photo illustrated building guide lists every step needed to complete the model with a text write up as well as a detailed illustration.

Buzz Bomb close up showing wing mount and landing gear attachment

Buzz Bomb close up showing wing mount and landing gear attachment

As is characteristic of all Stevens kits, there is not a set of full size plans on which you construct the model. Rather, the building guide discusses each step on how to assemble the given portion of the aircraft and glue it together.  The precise laser cutting allows for this type of build.

There were no surprises in the course of construction. This is a large plane compared to the indoor micro flyers I have made in the past.  With this increase in size it is critical that small building errors not creep into the finished section.

BuzzBomb fuselage showing laser engineered tab and lock construction

BuzzBomb fuselage showing laser engineered tab and lock construction

The one area where this did occur for me was in the attachment of the wing outer panels to the main wing assembly. Normally, the wing would be built directly over the plans to ensure a flat and true section.  As the wing is assembled with a tab and slot approach it is vital to ensure each section is flat and true before gluing the parts together.

While gluing the outer wing panels to the center section I did not properly check the alignment, allowing a differing amount of wing washout to be built into the right and left tips of the wing.

Buzz Bomb fuselage interior showing placement of servos and receiver

Buzz Bomb fuselage interior showing placement of servos and receiver

I caught this as I was eyeballing the overall fit of the finished, uncovered wing. I had to cut and re-glue each outer wing panel to ensure that all was flat and true.  Again, just be extra vigilant as you glue the final assembly of the wing together.

This issue will not come up with the tail surfaces as they are constructed on a flat building surface.

The nose moment of the BuzzBomb is a bit short in keeping with the original version. This was likely due to the heavy weight of the early gas engines.  Modern day electric motors are much lighter, thus the need for several ounces of nose weight to achieve the proper center of gravity location.  I used lead fishing weights purchased at Walmart, epoxied in place.

As a building tip, consider checking the balance before covering the nose section of the fuselage. You can then cut access holes to insert the nose weight and ensure it is securely glued in place prior to covering.

The remainder of the BuzzBomb went together well with no surprises. The finished plane looks great and grabs a lot of attention at the flying field.

My maiden flight went without incident. The plane promptly lifted off after a short takeoff run. The Stevens recommended engine provides plenty of thrust.  The controls were a bit sensitive as I employed full throw.  For my first flight I wanted a bit of extra control authority for the initial foray into the skies.  My plan will be to add a bit of exponential control around the center for a smoother rudder and elevator response.

Profile view of the Buzz Bomb forward fuselage showing rubber band landing gear attachment

Profile view of the Buzz Bomb forward fuselage showing rubber band landing gear attachment

There is one additional modification I will make on the model to allow for more predictable ground handling. I noticed from the beginning that the landing gear was mounted with the wheels tracking well forward of the landing gear attachment point.  This will lead to difficulties with the takeoff ground run as the aircraft has to overcome a “wheel barrow” effect with the aircraft’s center of gravity well behind where the wheels are in contact with the ground.

Completed Buzz Bomb wing structure

Completed Buzz Bomb wing structure

I am not 100% sure why the wheels were mounted so far forward on the original Buzzard Bombshell design. My guess is that in those early days of model flight there was a focus to protect the very valuable and expensive gas motors and propellers from damage with a hard landing or nose over during takeoff.  The engines produced a lot of thrust and the models took off quickly.  The gear mounting scheme allowed for protection of the motor during unpredictable free flight landings.

My plan is to adjust the landing gear mount to put the wheels more directly under the mounting point. I think this will allow for a predictable take off run.  Note also that the BuzzBomb’s rudder arrangement does not easily allow for a steerable tail wheel, which would assist with takeoff roll tracking a lot.

Overall I am completely satisfied with this remarkable laser-engineered model airplane kit. This is my seventh Stevens Aero kit, and they all maintain the highest of standards with engineering and flight characteristics.

The only down note for my model aviation activities is that I remain busy with my United Express airline flying. Once I get a bit of time in the workshop I look forward to adding a detailed build and flight video.