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Plans Cross Reference List

This work is based on “Build Your Own Airplane” by James R. Bede.

The table cross references part numbers to the drawing where the dimensions for that part are defined. It is based on a recent edition of the book. There may be omissions and/or errors.

Bob White

Currently the table has been checked through part 069. Parts above that are more likely to be in error (10/14/2001)

Most of the information in this table was contributed by Dave Arnholt.

To print this page use this PDF document.

Angle and Formed Parts Cross Reference

These are the parts in circles on the drawings

Part Number
(note 1)
Length if Applicable Material Number
(note 2)
Drawing No. Alloy or Material
(note 3)
Thickness Size (HeightXWidth)
001 62.25 227 BD-4-1-07 2024 0.063 6″x2″ channel
002 62.25 227 BD-4-1-09 2024 0.063 6″x2″ channel
003 38.38 32 BD-4-1-06 2024 0.063 2″x2″ angle
004 38.12 32 BD-4-1-06 2024 0.063 2″x2″ angle
005 43.31

32

BD-4-1-07 2024 0.063 2″x2″ angle
005a

36.8

222 BD-4-1-03 2024 0.063 1.94″x1.94″
006 43.31

32

BD-4-1-09 2024 0.063 2″x2″ angle
006A

36.8

222 BD-4-1-04 2024 0.063 1.94″x1.94″ open box
007

39.76

33 BD-4-1-11 2024 0.063 2″x2″ 76 deg angle
008 57.15

32

BD-4-1-09 2024 0.063 2″x2″ angle
008A 57.15 222 BD-4-1-01 2024 0.063 1.94″x1.94″
009 57.15

32

BD-4-1-07 2024 0.063 2″x2″ angle
009A 57.15 222 BD-4-1-03 2024 0.063 1.94″x1.94″ open box
010 29.6 221 BD-4-1-09 2024 0.063 1″X2″ channel
010A 29.6 221 BD-4-1-01 2024 0.063 1″X2″ channel
011 29.6 221 BD-4-1-07 2024 0.063 1″X2″ channel
011A 29.6 221 BD-4-1-03 2024 0.063 1″X2″ channel
012 29.75 32 BD-4-1-09 2024 0.063 2″x2″ angle
013 29.75 32 BD-4-1-07 2024 0.063 2″x2″ angle
014 16.62 32 BD-4-1-09 2024 0.063 2″x2″ angle
015 16.62 32 BD-4-1-07 2024 0.063 2″x2″ angle
016 39 34 BD-4-1-12 2024 0.063 2″x2″ 122 deg. angle
017

67.18

31 BD-4-1-07 2024 0.063 1.5″x 1.5″ angle
018

67.18

31 BD-4-1-09 2024 0.063 1.5″x 1.5″ angle
019 7.4 30 BD-4-1-07 2024 0.063 1″x1″ angle
020 7.4 30 BD-4-1-09 2024 0.063 1″x1″ angle
021 39 31 BD-4-1-11 2024

0.063

1.5″x 1.5″ angle
022 20.75 31 BD-4-1-09 2024 0.063 1.5″x 1.5″ angle
023 20.75 31 BD-4-1-07 2024 0.063 1.5″x 1.5″ angle
024 28.75 30 BD-4-1-11 2024 0.063 1″x1″ angle
025 28.75 30 BD-4-1-11 2024 0.063 1″x1″ angle

26

116.5

31

BD-4-1-10

2024

0.063

1.5″x1.5″ angle

27

116.5

31

BD-4-1-08

2024

0.063

1.5″x1.5″ angle

028 6.5 34 BD-4-1-06 2024 0.063 2″x2″ 122 deg angle
029 30.4 30 BD-4-1-06 2024 0.063 1″x1″ angle
030 44.2 30 BD-4-1-06 2024 0.063 1″x1″ angle
031 21.4 30 BD-4-1-06 2024 0.063 1″x1″ angle
032 37.72 30 BD-4-1-06 2024 0.063 1″x1″ angle
033 12.7 30 BD-4-1-06 2024 0.063 1″x1″ angle
034 31.8 30 BD-4-1-06 2024 0.063 1″x1″ angle
035 6.7 30 BD-4-1-06 2024 0.063 1″x1″ angle

036

59.56

31

BD-4-1-10

2024

0.063

1.5″x1.5″ angle

036a

63.26 (note 4)

31

BD-4-1-10

2024

0.063

1.5″x1.5″ angle

037

59.56

31

BD-4-1-08

2024

0.063

1.5″x1.5″ angle

037a

63.26 (note 4)

31

BD-4-1-08

2024

0.063

1.5″x1.5″ angle

038

4.75

33

BD-4-1-11

2024

0.063

2″x2″ 70 deg. angle

039 30.4 30 BD-4-1-11 2024 0.063 1″x1″ angle
040 43.3 30 BD-4-1-11 2024 0.063 1″x1″ angle
041 21.4 30 BD-4-1-11 2024 0.063 1″x1″ angle
042 38.32 30 BD-4-1-11 2024 0.063 1″x1″ angle
043 12.7 30 BD-4-1-11 2024 0.063 1″x1″ angle
044 32.05 30 BD-4-1-11 2024 0.063 1″x1″ angle
046 20.6 30 BD-4-1-10 2024 0.063 1″x1″ angle
047 20.4 30 BD-4-1-08 2024 0.063 1″x1″ angle
048 13.1 31 BD-4-1-10 2024 0.063 1.5″x 1.5″ angle
049 13.1 31 BD-4-1-08 2024 0.063 1.5″x 1.5″ angle
050 57.75 31 BD-4-1-10 2024 0.063 1.5″x 1.5″ angle

051

57.75 31 BD-4-1-08 2024 0.063 1.5″x 1.5″ angle
052 21.35 30 BD-4-1-09 2024 0.063 1″x1″ angle
053 21.35 30 BD-4-1-07 2024 0.063 1″x1″ angle
054 33.9 30 BD-4-1-09 2024 0.063 1″x1″ angle
055 33.9 30 BD-4-1-07 2024 0.063 1″x1″ angle
056 33.35 30 BD-4-1-09 2024 0.063 1″x1″ angle
057 33.35 30 BD-4-1-07 2024 0.063 1″x1″ angle
058 15.36 30 BD-4-1-10 2024 0.063 1″x1″ angle
059 15.36 30 BD-4-1-08 2024 0.063 1″x1″ angle
060 32.6 30 BD-4-1-10 2024 0.063 1″x1″ angle
061 32.6 30 BD-4-1-08 2024 0.063 1″x1″ angle
062 11.8 30 BD-4-1-10 2024 0.063 1″x1″ angle
063 11.8 30 BD-4-1-08 2024 0.063 1″x1″ angle
064 22.3 30 BD-4-1-10 2024 0.063 1″x1″ angle
065 22.3 30 BD-4-1-08 2024 0.063 1″x1″ angle
066 14.1 30 BD-4-1-10 2024 0.063 1″x1″ angle
067 14.1 30 BD-4-1-08 2024 0.063 1″x1″ angle
068 8.15 30 BD-4-1-09 2024 0.063 1″x1″ angle
069 8.15 30 BD-4-1-07 2024 0.063 1″x1″ angle
070 n/a 31 BD-4-1-02 2024 0.063 1.5″x 1.5″ angle
071 n/a 31 BD-4-1-02 2024 0.063 1.5″x 1.5″ angle
071a 4.75 30 BD-4-1-02 2024 0.063 1″x1″ angle
072 n/a 31 BD-4-1-02 2024 0.063 1.5″x 1.5″ angle
073 n/a 31 BD-4-1-02 2024 0.063 1.5″x 1.5″ angle
073A 4.75 30 BD-4-1-02 2024 0.063 1″x1″ angle

074

41.5 230 BD-4-1-02 2024 0.063 Fuselage “V” angle
075 12.38 32 BD-4-1-04 2024 0.063 2″x2″ angle
076 12.38 32 BD-4-1-01 2024 0.063 2″x2″ angle
077 19.75 31 BD-4-1-07 2024 0.063 1.5″x 1.5″ angle
078 19.75 31 BD-4-1-09 2024 0.063 1.5″x 1.5″ angle

079

n/a

28

BD-4-1-04 2024 0.063 n/a

080

n/a

28

BD-4-1-04 2024 0.063 n/a
081 32.8 30 BD-4-1-05 2024 0.063 1″x1″ angle
082 1.75 32 BD-4-1-04 2024 0.063 2″x2″ angle
083 1.75 32 BD-4-1-04 2024 0.063 2″x2″ angle

087

1.75

64

BD-4-1-02

6061

0.125

1″x1″ angle
091 12.6 38 BD-4-1-04 4130 0.063 2″x2″ sheet
091a 12.6 30 BD-4-1-04 2024 0.063 1″x1″ angle
092 12.6 38 BD-4-1-04 4130 0.063 2″x2″ sheet

Miscellaneous Parts Cross Reference

These are the part numbers in rectangles on the drawing

Misc Part Numbers
(note 5)
(in the rectangles)          

01

4.5

228

BD-4-1-05

6061

0.125

1.75″x2.25″ rect. tube

02

4.5

228

BD-4-1-05

6061

0.125

1.75″x2.25″ rect. tube

03

4.5

228

BD-4-1-05

6061

0.125

1.75″x2.25″ rect. tube

04

4.5

228

BD-4-1-05

6061

0.125

1.75″x2.25″ rect. tube

NOTES

  1. These are the parts that are in circles on the drawings

  2. These are the numbers that are in a hexagon on the drawing. Callouts are on page 142.

  3. This is the base material. You also need to be aware of the hardness or other properties called out in the drawings.

  4. This is not the maximum dimension of this piece – see drawing.

  5. These are the numbers in rectangles on the drawings.

BD-4 Hex # to Part # Cross Reference

Click here for a cross reference between the hex number and the associated Bede Part numbers.

Plans Revisions

I got curious about what the exact differences between the plans and the book drawings were, so I compiled a list showing what is the same and what s different. I have attached it as an Excel spread sheet. I can’t guarantee there aren’t any errors. Some of the print is hard to read. Both were purchased from Jim Bede in 2000.

Bob White

Num.  Included  Title  Last Revision Date 
Book Plans Book Plans
BD-4-0-01 x x THREE VIEW 05/01/73  
BD-4-1-01 x x MASTER-GUSSETS AND ANGLES 05/04/70  
BD-4-1-02 x x FUSELAGE ASSEMBLY-FORWARD 08/10/76  
BD-4-1-03 x x FUSELAGE-UPPER-FORWARD 05/26/70  
BD-4-1-04 x x FUSELAGE NO. 2 08/12/76  
BD-4-1-05 x x TEMPLATES, MISC. 05/04/76  
BD-4-1-06 x x TEMPLATES – FUSELAGE BOTTOM 08/10/76  
BD-4-1-07 x x TEMPLATES – LEFT SIDE FORWARD 05/04/76  
BD-4-1-08 x x TEMPLATES – REAR LEFT SIDE 05/04/76  
BD-4-1-09 x x TEMPLATES – RIGHT SIDE FORWARD 05/04/76  
BD-4-1-10 x x FUSELAGE – REAR RIGHT SIDE 05/04/76  
BD-4-1-11 x x TEMPLATES – TOP 05/04/76  
BD-4-1-12 x   BASIC FUSELAGE MASTER DIMENSION 05/12/70  
BD-4-1-13 x x ENGINE MOUNT INSTALLATION LYCOMING O-235 THRU O-320 (CONICAL) 08/10/76  
BD-4-1-14 x   ENGINE MOUNT DYNAFOCAL (OPTIONAL DRAWING (SHEETS 1 AND 2) 30/09/72  
BD-4-1-15 x x DOORS 05/18/70  
BD-4-1-16 x x SKIN AND LEXIGLASS 08/19/76  
BD-4-1-17 x x AFT FUSELAGE MISC. 08/20/76  
BD-4-1-18 x x COWLING 05/18/70  
BD-4-1-19 x x FUSELAGE MISC. N/A  
BD-4-2-01 x x LANDING GEAR – MAIN 08/24/76  
BD-4-2-02 x x LANGING GEAR – NOSE NO.1 05/19/76  
BD-4-2-03 x Note4 LANDING GEAR – NOSE NO.2 05/19/70  
BD-4-2-04 x   LANDING GEAR – CONVENTIONAL (SHEETS 1 AND 2) OPTIONAL DRAWING) 09/05/69  
BD-4-2-04 #2 x   TAIL WHEEL ASSEMBLY           (SEE NOTE 1. BELOW) 09/24/69  
BD-4-2-05 x   LANDING GEAR – NOST STRUT (OPTONAL DRAWING) 08/28/76  
BD-4-2-06-1   x MAIN LANDING GEAR   02/07/96
BD-4-2-07   x MAIN LANDING GEAR   02/07/96
BD-4-2-08   x BD 4 MAIN GEAR PARTS   04/17/96
BD-4-2-09   x MAIN LANDING GEAR   02/07/96
BD-4-2-10   x MAIN LANDING GEAR WELDMENTS   06/22/99
BD-4-3-01 x x AILERON AND ELEVATOR CONTROL NO.1 05/19/76  
BD-4-3-02 x x ALERON AND ELEVATOR CONTROL NO.2 05/19/76  
BD-4-3-03 x x RUDDER CONTROL NO.1 05/27/76  
BD-4-3-04 x x FLAP SYSTEM 05/19/76  
BD-4-3-05 x x TRIM SYSTEM 05/19/70  
BD-4-3-06 x x RUDDER CONTROL NO.2 06/08/73  
BD-4-3-07 x   WHEEL CONTROL (OPTIONAL DRAWING) 08/30/76  
BD-4-3-08 x   WHEEL CONTROL (OPTIONAL DRAWING) 12/22/68  
BD-4-4-01 x x WING ASSEMBLY NO.1 05/20/76  
BD-4-4-02 x x WING ASSEMBLY NO.2 05/20/70  
BD-4-4-03 x x WING ATTACHING AND FOLDING 04/01/69  
BD-4-4-04 x x WING ASSEMBLY 08/30/76  
BD-4-4-05 x   WING RACK 03/18/70  
BD-4-5-01 x x HORIZONTAL STABILIZER 10/10/68  
BD-4-5-02 x x HORIZONTAL STABILIZER 05/20/76  
BD-4-5-05 x x VERTICAL STABILIZER AND RUDDER (SHEETS 1, 2, AND 3) 6/20/7? 06/20/73
BD-4-6-01 x x ENGINE BAFFLES FOR LYCOMING O-235 THRU 0-320 04/07/69  
BD-4-6-02 x x ENGINE BAFFLES FOR LYCOMING O-235 THRU 0-320 06/03/76  
BD-4-6-03 x x ENGINE BAFFLES FOR LYCOMING O-235 THRU 0-320 04/07/69  
BD-4-6-04 x x FUEL SYSTEM 06/03/70  
BD-4-6-05 x x BRAKE AND AIRSPEED SYSTEM 05/21/76  
BD-4-6-06 x   180 HP CARB HEAT BOX (OPTIONAL DRAWING) 12/04/70  
BD-4-6-07 x x WIRING DIAGRAM (ORIGINALLY BD-4-6-06) NO DATE 02/19/70
BD-4-6-08 x x COWL MOD. 180 HP LYCOMING INSTALLATION 08/28/76  
BD-4-7-01 x x SEATS 05/21/76  
BD-4-7-02 x x INSTRUMENT PANEL AND ENGINE CONTROLS 05/25/70  
BD-4-7-03 x   BAGGAGE COMPARTMENT (OPTIONAL DRAWING) 02/09/70  
SK-21   x PANEL RIB (ALUMINUM)   02/13/69
SK-56   x WING TIP   04/10/74

 

NOTE 1: THIS DRAWING IS LISTED IN THE MASTER LIST AS BD-4-2-04 SHEET 2, BUT THE ACTUAL DRAWING HAS A DIFFERENT TITLE

NOTE 2: SOME DATES WERE NEAR ILEGABLE AND I MADE THE BEST GUESS THAT I COULD. ALSO, THE PLACEMENT OF THE MODIFICATION BLOCK VARIED AND IT IS POSSIBLE THAT I MISSED ONE OR TWO.

NOTE 3: SOME OF THE 1976 DATES MAY BE 1970 DATES. THE ZERO HAS A LINE EXTENDING ABOVE AND I INTERPERETED IT TO BE A SIX. OTHERS WERE CLEARLY A SIX.

NOTE 4: DATES ARE DIFFERENT BUT NOTES ON REVISIONS ARE THE SAME. THE BLUEPRINT (PLANS) LOOKS LIKE THE DATE MAY HAVE BEEN CHANGED FROM 70 TO 76.

NOTE 5: THE DATE WAS ACTUALLY CLEARER IN THE PLANS THAN IN THE BOOK. THIS IS A THREE SHEET DRAWING, AND THE DATE SHOWN IS THE LATEST DATE ON ANY OF THE THREE SHEETS

(Ed.: I marked the lines where the book differed from the plans with yellow).

Bede Corp. Newsletters

The Bede Corp. used to distribute newsletters for the BD-4 in 1970 and later. I received some of them from Lance Schlichter. They are all scanned in and I’m in progress making them available as PDF.

It seems we are missing some of the newsletters.  If you have them, please contact us. However, the current table does not yet show all the newsletters we have. We will update this list soon.

You can download all newsletters in a single ZIP archive. Warning! This file is 82.6 MB large!

For those with a slow internet connection I can send out a CD.

 

HTML1) 2) Date Status
Vol. 1 No. 1 Vol. 1 No. 1 1970 only PDF
Vol. 1 No. 2 Vol. 1 No. 2 1970 only PDF
Vol. 1 No. 3 Vol. 1 No. 3 1970 only PDF
Vol. 1 No. 4 Vol. 1 No. 4 1970 only PDF
Vol. 1 No. 5 Vol. 1 No. 5 1970 only PDF
Vol. 1 No. 6 Vol. 1 No. 6 1970 only PDF
Vol. 1 No. 7 Vol. 1 No. 7 1970 only PDF
Vol. 1 No. 8 Vol. 1 No. 8 1970 only PDF
Vol. 1 No. 9 Vol. 1 No. 9 1970 only PDF
Vol. 1 No. 10 Vol. 1 No. 10 1970 only PDF
Vol. 1 No. 11 Vol. 1 No. 11 1970 only PDF
Vol. 1 No. 12 Vol. 1 No. 12 1970 only PDF
Vol. 2 No. 1 Vol. 2 No. 1 Dec. 1970 only PDF
Vol. 2 No. 2 Vol. 2 No. 2 Jan, Feb. 1971 only PDF
Vol. 2 No. 3 Vol. 2 No. 3 Mar., Apr. 1971 only PDF
Vol. 2 No. 4 Vol. 2 No. 4 May, Jun. 1971 only PDF
Vol. 2 No. 5 Vol. 2 No. 5 July, Aug. 1971 only PDF
Vol. 2 No. 6 Vol. 2 No. 6 1972 only PDF
Vol. 2 No. 7 Vol. 2 No. 7 1972 only PDF
Vol. 3 No. 1 Vol. 3 No. 1 in progress
Vol. 3 No. 2 Vol. 3 No. 2 in progress
Vol. 3 No. 3 Vol. 3 No. 3 in progress
Vol. 3 No. 4 Vol. 3 No. 4 in progress
No. 1 No. 1 Dec. 1977 in progress
Vol. I Vol. I Jan. 1978 in progress
Vol. II Vol. II Feb. 1978 in progress
Vol. III Vol. III Mar. 1978 in progress
Vol. IV Vol. IV Apr. 1978 in progress
Vol. V Vol. V May 1978 in progress
Vol. VI Vol. VI Jun. 1978 in progress
Vol. VII Vol. VII Jul. 1978 in progress
Vol. IX Vol. IX Sep. 1978 in progress
Vol. X Vol. X Oct. 1978 in progress
Vol. XI Vol. XI Nov. 1978 in progress
Vol. XII Vol. XII Dec. 1978 please provide3)
Vol. XIII Vol. XIII Jan./Feb. 1979 in progress
? ? ? only PDF

 

1) The HTML version is an online web page (just like this page). If you click on the number it will open in the browser and you can go back. The HTML pages are converted from the paper copies of the newspapers. This conversion is not 100% accurate. Check the PDF document for the real thing.

2) PDF is a Adobe Acrobat document. It is a graphical image of the print-out. You can download the PDF document and print it out off-line. You’ll need Adobe’s PDF Reader

3) We are missing this newsletter. If you happen to have it, please send it to us and we will make it available here. Thanks!

Fuel Tanks

All fuel system pages

Roger Mellema

Fuel cell leakage

The BD-4 has more than it’s share of fuel cell problems but don’t feel like the Lone Ranger – many airplanes have the same problem. The best way to insure good cells is to prepare the glass panels before wing assembly. There are many people who think. sloshing material is a lot better than it really is and hope it will fill all the cracks and pin holes. The panels should be inspected and the best ones chosen for fuel. These should be checked carefully for flaws and these should be fixed on the inside of the wing using fiberglass (some builders lay another layer of glass on the two end ribs of the tank). The inside of the cells should be sanded until the entire surface is roughed up (don’t sand into the cloth). The surfaces should be cleaned more than once with acetone or MEK – not just wiped but flow it on with one cloth and wipe it dry with another. I then painted four coats of thinned slosh material on all surfaces except the 1.5 inch edge to be glued. Make sure all the pin holes get filled. After the wing has been glued together, the tanks are sloshed with unthinned slosh. I like to keep turning the wing while a vacuum cleaner, hooked backwards, blows warm air into the fuel gauge hole.

This helps the slosh dry evenly on all surfaces. Be very careful to keep sparks from getting anywhere near the fumes as they are very explosive. I know of one person who blew up a wing.

Some people coat the entire outside of the tank area with a light layer of fiberglass. This works very well but the last time I just put 2 inch strips of glass over the cell joints. The 2216 used on the wings does not have very good peel strength. I had a couple joints come loose on my first BD-4. Av-gas eats asphalt beautifully so I quickly flew away before they decided to charge me for it. Make sure you fuel test your wings before you go to fly. Fill them up to the top and let them set for at least two days. It eaves a lot of embarrassment come test flight time.


Roger Mellema
Newsletter #13 (March 86)

Paul Wood from Lincoln, NE recently purchased a BD-4 and is having some trouble with leaky fuel tanks and other things. Sorry I haven’t written back sooner, Paul, but I will answer your questions here as maybe other readers have the same problem.

The fuel tank problem is a very common one and many people who buy a used Br) are told by the seller that “it never leaked when I had it”. This could be true but knowing BD-4’s, I rather doubt it. The leaks that occur in the outside skin are usually very easy to correct by putting some sealant over the leaky spot on the inside of the tank or by putting a small fiberglass patch on the outside.

Leaks that occur along the rear of the wing are usually caused by not sealing the flap/aileron attachment brackets properly. These again are not too difficult to fix if you don’t mind taking the flaps and ailerons off and mettind in and using some Pro-Seal to fix the oroblerii. By the way, I have seen builders pour unbelievable ariic-urits of slosh into the wine in the hopes of sealing a leak such as this and never oettina it done. Slosh is really only good for coating surfaces so oas can’t attack therii and sealing piri holes. The hardest leaks I’ve seen to seal are the ones that Occur in the ribs at each end of the fuel tank. The inboard rib seems to be the worst problem. This may be because of the slight flexing of the tubular spar which will be worse in the vicinity of the inboard rib than by the outboard rib. When you have a seep in one of these ribs, it usually requires cutting a hole in the last cell of the fuel tank, cleaning all the gunk (sloshing material and 2216 glue, etc.) off of the rib and then painting it with brushable Pro-Seal.

Before doing anything drastic, check the hose fittings and the fuel sender gasket to be sure they are not leaking. it sometimes helps to clean the area with solvent (or soap and water, or diesel fuel) and blow a thin layer of white flc-ur or powder oritc, the surfaces to make it easier, to see where the leak actually is. It is very difficult to tighten the fuel lines to the fittings that go into the tank so this is a frequent source of leaks. I like to coat the rotarig surfaces of the fittings with a little Pro-Seal to make sure they don’t leak.. Par-t of the problem here is that Bede supplied 2000 lb hydraulic lines to be used as fuel lines as they are extremely stiff. It would be a very good idea to get rid of these and put in something reasonable. The fuel pressures in this area are extremely small. When working with the hoses be careful to riot turn the fittings that go iritc- the tank as that will certainly cause leaks – it is very difficult to work on the aft fitting, sometimes requiring griridirig down wrenches etc..

When cleaning the ribs, be sure to pay special attention to the area j,ust around the spar. This is a very difficult area to get at but is by far the riiost iriiportant. The wing cell should be cut into so that you have good access to this area. If you think you are going to out a 6 inch hole in the top of the wing and work throumh it, you are very riiistakeri. What it really requires is to cut a hole in the BOTTOM of the cell that noes 12 or more inches forward of the spar and 12 or more inches aft of the spar. It should be cut to withir, 1.5 inches of each rib. The panel can be cut in an ‘HI shape with the center of the “H parallel with the spar. You will then have to find a way to hold the ‘HI open so that you car, work freely. It really is a lot easier to work if the whole panel is cut out but it is a little easier to close up the hole again if everything is not cut away. Next you should use acetone or MEK and/or a flat scraper (looks like a wood chisel) to scrape away the slosh around the hole and from the entire rib. Don’t get lazy and quit before the job is done – set everything up so you can sit down and take your time while doing this. It helps to use a trouble light held on the other side of the rib you are cleaning to see where you aren’t getting it right. This is a lot easier on the inboard rib where both sides are accessable.

The next job is to coat the rib with brushable Pro-Seal. A couple of good even coats should do it. The light will come in handy again here to see areas that have been missed. The fiberglass skin car, be closed up again by getting the cutout part to lay right and then covering the cut with about three layers of 8 oz fiberglass cloth (at least 2 inches wide) and polyester, r,esiri. The very early, very white opaque wing panels were made with epoxy and you will have to experiment to see what will work with these. If you think you need rilore strength than the fiberglass patch provides you can put manner- to the gas cap installation.

I guess the one point I want to make clear is that you CANNOT fix a leaking tank by dumping more slosh into it. I have seen a couple thousand dollars in slosh go down the drain with out doing much r3c-od. A couple of times I have seen the tanks stay sealed for a month or two and then take up right where they left off.

Frequently Asked Questions

Q: Is the BD-4 a true 4-seater?
A: Only with the one of the fuselage modification. With the original configuration, the back seats are for small people. Tall people will fit too but it is rather snuggly (see this picture, this is an unmodified fuselage). I’ve flown on trips on the back seat and found it to be quite comfortable when I had the bench for myself. A number of BD-4s have consistently shown up at the fly-ins with four people on board.

Q: Can the BD-4 be built from plans?
A: Yes, and there are a number of flying BD-4s that were build from plans. The material for most parts can be purchased from regular sources, and of course from the Bede Corp. Some parts have to be welded. If you can’t do it yourself there are other builders who can help you out. Note that the BD-4 was sold as a kit and the plans assume you have received all parts and don’t go into much detail how to acquire and build from the raw material. This website is trying to fill in here and the builder’s community is pretty good with giving answers when questions arise from reading the plans.

Q: How fast is the BD-4 really?
A: This greatly depends on the configuration. Factors such as power plant, landing gear configuration (tricycle or tail wheel), fairings, a rounded windshield let the cruise speed vary between 140 MPH and 200 MPH. Expect 140 MPH (or even less) with a 150 HP engine, a tricycle and little to no fairings. Expect 180 MPH (or even a little faster) with a IO360, wheel pants, the rounded windshield and everything neatly faired in. There are sample BD-4 flying with a fuel efficiency of around 20 MPG. This is rarely beat by other 2+2 seaters.

Q: Is the BD-4 all metal?
A: The fuselage and empennage is metal. However, the original kit had composite wings. These composite wings very often suffered from leaking fuel cells. A lot of builders have built metal wings. Some purchased the “Murphy Wings”. TVAP’s sells wing kits for around $5,000. You can buy metal ribs from Dream Aircraft and D&E Aircraft Services. Together with the spars from Dream Aircraft (see supplier page) and sheet metal you can build your own wings. Bede’s plans contain drawings for metal wings. John Raffensparger also sells plans for metal wings.

Q: Which engine can I use?
A: The BD-4 is one of the most versatile designs, especially in regards to the power plant.  It has been flown with numerous certified and other engines (i.e. autoconversion engines). The engine of your choice should not have less than 150 HP. The most commonly used engine it the Lycoming IO320 and IO 360. But there are quite a few with Ford V6 auto engines. For engines much heavier than the IO360 a fuselage stretch might be in order.

Q: Is it advisable to buy a 20 year old project? Any age related issues to be considered?
A: This depends on the project. Generally the parts don’t fall apart over time. However, do look for corrosion. I’ve heard of a project where mice have nested and their urine weakened the fuselage skin to an extent that one could poke through it with the bare finger. Others have reported corrosion on the inside of the wing spars. If the windows are build of Lexan they will probably have to be replaced. If the composite wings are already assembled check for fuel leaks (and ask how the builder treated the fuel cells). Also, a really old project might miss some of the numerous modifications.  I personally bought two 20 year old projects. The one was an unfinished project. The parts are in a very good shape. Some corrosion but nothing to worry about. The second was a plane that has been flown over 1200 hours. The fuselage is in an excellent condition. When you consider buying an unfinished project be real careful to uncover building mistakes.

Q: How much fuel will fit into the tanks?
A: The fuel cells are located in the wing (wet wing design). The size of the tanks depend on how many sections (in between two ribs) you want to flood. A section fits about 7 gal. Most builders use 3 to 5 cells for each wing (equaling app. 40 to 80 gal total). But there are others that use more (up to the 100 gal. ofJim Huber‘s plans built plane).

Q: What is the useful load for the BD-4?
A: This depends on two factors: empty weight (1,200 lbs ~ 1,500 lbs) and gross weight. Latter number in turn depends on which wing and center spars you use and how long your wings are. The weakest link with long wings and the original spars are the wing spars (not the center spar). In this configuration gross weight is 2,200 lbs or less to remain within the utility class. If you use the spars from Dream Aircraft you may increase the gross weight to max. 2,500 lbs. In addition to the wing spar, for a high gross weight the stability of the landing gear is also of concern. With a beefed up landing gear (Bede’s modifications call for this) a gross weight of 2,500 lbs seems unproblematic. Thus, in case you shoot for a high useful load you can achieve around 1,000 lbs (including fuel).

Q: I heard the landing gear is too weak. How can one beef it up?
A: Both the landing gear box and the gear should be modified to handle the additional weight of nowadays BD-4’s in relation to the original BD-4 of 1969.  There are various articles in the newsletters how to beef up the landing gear box. The original landing gear is soft and tends to sag. Again, the newsletters discuss several fixes. You may also buy a ready-to-go-in landing gear from Dream Aircraft.

Q: Is the BD-4 hard to fly?
A: No. However, it has a rather high stall speed if the original (short) wings are used. You can improve the stall speed by having longer wings, extending the chord length of the flaps by about 2″ and enable a 40% flap setting.

Q: I’ve heard the BD-4 is an unsafe aircraft because there have been many accidents that were caused by fuel starvation. Is this true?
A: It is true that there have been accidents because of fuel starvation. Mostly this happened in high angle of attack situations shortly after take-off. The wings have no dihedral which makes the fuel pick-up a little trickier. If you build the fuel system according to the plans, run fuel flow tests on the ground and don’t take off with little rest fuel in the tanks you’re safe. Some insurer ask for a header tank because of reported accidents. Refer to the fuel system section for more information.

Q: There seems to be some discussions over the structural stability of the wing spars. Is this of concern?
A: It is of concern if you build the longer wings with the original spars. You can either lower the gross weight to i.e. 2,200 lbs or buy the “Super Tube” fromDream Aircraft. Note that there is no reported case of an in-flight failure of the wing spars after 20 or so year of using this system. There are also planes with long wings and original spars that have been flown for more than 10 years. Refer to the back issues of the newsletter and the online discussion.

Q: Where can I buy the plans? What additional information is available?
A: The plans are sold by Jim Bede (www.bedecorp.com). There is also a book. The book contains most of the plans (in a smaller scale) and is generally sufficient to build the plane. There are differences between the plans and the book. Refer to the revision page for more information.

Q: Why is the BD-4 so fast and fuel efficient? Where is the catch?
A: The catch has to be the size of the cabin if you compare it with other (real) 4-seaters. This keeps the frontal area small and thus the drag. However, for a 2+2 seater you’ll find the cabin surprisingly spacious. The low drag wing profile makes for a fast cross country machine. The approach speed is higher than that of a Cessna 172. It seems not advisable to put a BD-4 on floats.

Q: What are the dimensions of the cabin?
A: Width=42 in., height= 41 in., length=98 in.

Q: I’ve heard about a small and larger tail (vertical stabilizer). What is the difference?
A: The first BD-4s had a smaller vertical stabilizer with a split rudder where the rudder did not go all the way up to the tip of the stabilizer. In 1970 the Bede Corp. came out with an ‘optional’ design improvement, the ‘larger tail’. This address the (for some pilots) inadequate rudder efficiency and directional stability (see additional information).