Since the issue of the first plans by Jim Bede in the 1970
there were numerous modifications published, both by Bede and other designers
The last column in the following table lists (some of) the builders who have adapted a specific modification. When you click on their names there is a good chance that there is a picture of their aircraft and the modification visible.
|Modification||Description||Builders Using It|
|Bede Corp's modifications||I believe there are 76 modifications that were published by Bede. Some are considered 'mandatory' (although this does not have a legal background for an experimental plane).||All builders should use them.|
|Metal wings||This is one a popular modification to the original composite wings. Bede's plans (later editions) include plans and instructions for metal wings (using 0.020 Al 2024-T3). You can buy metal ribs from Dream Aircraft and a full set for metal wings from TVAP (see supplier's page).||Fred Hinsch (Murphy plans), John Steere (Raffensparger plans) and many others|
|Nose gear||The original nose
gear was known to break, especially with a heavier engine. Alternative
proven solutions are:
||Ron Vance, Mike Borgelt, see his description.|
fuselage extension makes the fuselage longer. The motivation is either
to balance a heavier engine with a longer lever of the tail or/and to
increase the cabin space for the rear seats. With a 18" fuselage
extension the BD-4 is a true 4 seater.
This picture shows John Thompson retrofitting his BD-4 with an fuselage extension. The extension is just aft of the rear door post. Click on the picture to see a full sized image. It is taken out of Hugo Schneider's newsletter from 1996.
This is Mac Mcginnis' BD-4.
|Ray Ward and a number of others. The pictures of Ray's BD-4 were taken before he incorporated the fuselage extension.|
|Lloyd Brekke's fuselage Modification||
does not change the length of the fuselage but increases the headroom
of the back seats. Please refer to the supplier
page for contact.
|Stronger and Heavier powerplant|| To balance a heavier
power plant a common way to get the CG back into it's limits is to apply
a fuselage extension, like the one suggested by Ray Ward.
Ray Ward also wrote the book "Fun and Forced Landings with V/8 Power" in which he describes the modifications to build in a bigger and heavier power plant.
|Curved windshield||Refer to the newsletters, also there is a good document with installation instructions and drawings by Mark Miller, it can be purchased by GeeBee Canopies in WA||Steve Craigle, Steve Mahoney, John Steere, Deene Odgen, Craig Evans, Ron Vance and many others.|
|Longer Wings||Longer wings to lower the stall speed, improve climb rate, increase service ceiling (Roger Mellema used a still existing set of full wing molds to produce them out of composite; the molds are probably at Crest Airpark, WA)||Steve Craigle (composite), Fred Hinsch (metal), John Steere (metal) and many others|
|Increased flaps area||See extended flap chords in newsletter #17||John Steere, Lary Seibold, others|
|Push-pull rods instead of control cables||See drawing of the bellcrank; another mentioning in newsletter #17||Steve Craigle and many others|
|Ball bearings for control system bellcranks and pullies||See picture at the bottom of Jim Huber's seat page||Jim Huber, Steve Craigle and many others|
|Fuel header tank||John Steere, Steve Craigle and many others|
|Modificated fuel vents||to pressurize the tanks||Steve Craigle and many others|
|Fuel flapper valves||These valves are to keep the fuel level in the inboard fuel cell high and prevent unporting. Steve Craigle sent a little drawing showing how he used a weight on a lever to keep some closing pressure on the flap. I can't find that drawing right now. But if you need it I'll look again or ask Steve to make another one. The image is from Gord's wing.||Steve Craigle and Gordon Hudson, Scott DeGaynor and others|
|Aileron spades||Modified counterweights for ailerons to decrease adverse yaw||Carlos Serodio, Steve Craigle and others|
|Top hinged doors||Roger's newsletter #12;||Steve Mahoney, Larry Seibold, Ron Vance and others|
|Double side and door windows||To reduce noise, see Roger's newsletter #20||Steve Mahoney|
|Single adjustable front seats||Jim Huber, Steve Craigle, Dave Anderson, Ron Vance and many others|
|Modified strip to cover the gap of flaps and ailerons||See picture||Holger Stephan|
|Yokes instead of control sticks||John Steere, Ken Kopp and others|
|Rudder trim tab modifications||See newsletter||John Steere, Carlos Serodio and others|
|Fully transparent doors||See newsletter||Larry Seibold, Dan Cowan, Richard Martin|
|Different main gear||John Raffensparger used Cessna main gears. Dream Aircraft sells improved main gears. See supplier's page.|
|Stiffed up main gear||Al 2024 bolted to the original 2024 aluminum gear leag to prevent sagging.||Steve Craigle and others|
|Main gear box||
|Solid landing gear link||This modification replaces the rubber "donat" with a solid aluminum link. See Roger's newsletter #20||Steve Craigle and many others|
|Beefed up landing gear box||Roger's newsletter #20||Steve Craigle and many others (hardly anybody flies without)|
|Longer and stronger center spar||Dream Aircraft and TVAP sells them, Jim Bede's BedeCorp plans to start offer them in Q1/'04. They allow a higher gross weight for the extended wing span.|
|Corrosion Protection||Bede's book does not talk much about corrosion protection. However, corrosion can be serious issue and alodining and priming the fuselage structure is highly recommenced. Very important is also the corrosion protection of the wing spars. There were a number of badly corroded wing spars appearing in the past years. Especially the fuel cell area is prone to corrosion.|
|Vortex Generators||Both Richard and Steve had really good results
reducing the stall speed with VGs. In Steve's case there wasn't even a
slowing down in cruise.
See also: Richard's VG page, Steve's VG page
|Richard Martin, Steve Craigle, Fred Hinsch|
|Leading Edge Cuffs||Richard Martin developed and tested these and was able, in conjunktion with his VGs to reduce stall speed to around 40 MPH!||Richard Martin|
Other Sources for Modifications: