Plans Updates for plans dated prior to Jan 2003

Aug 18, 2004 The tail wheel springs and safety wire can wear (so check them), also the rudder/tail wheel control horn (on the bottom of the rudder) could use a heavier and longer arm. Suggested upgrade is to use a 5" long 4130 tube x 5/16" x .058 control arm on the rudder/tail control horn assembly. If the tail wheel losses its linkage you would not be in danger in the air but ground handling will become difficult. The link from the bottom of the rudder control horn to the 1/2" bobbing link steering bar needs 2 springs (one on each side and safety wire running inside the spring with 1/4" slack) because of the changing distance as the link moves but the linkage from the steering bar link down to the tail wheel horn can be heavy safety wire (.041") on each side (just transfers motion with no changing distance). I noticed a friend of mine had used a couple of spring door springs as you see in the first picture, they work well but are a bit heavy. Note that the picture has the tail folded and the elevator control arm is not hooked up. Here is a BRS parachute installed, notice that it is off center to allow the aileron control tube to pass un-obstructed.

Jan 1, 2002 A control stop should be in place on the tailpost to relieve elevator control pressure when the plane is at rest, be sure that the control stop cannot come loose and interfere with the controls during flight and does not limit the range of motion. There is more than one way to do this but there should be an at rest control stop in the elevator system to keep the system from being under load all of the time. See Dia-CO-15

Aug 31, 2008. Update on the wing spar distance and measuring stick. Please use 45" or 45 1/2" for this spacing instead of 45 3/4" or 46". The reason I am making this change is that the use of 4 ft. ribs are having a hard time reaching both spars especially when the spar size may change from 3" to 2 1/2, also the ribs need to be trimmed for your airplane as you make them and this insures a closer match when suppliers don't hit the 4' mark when cutting your order.

Jan 22, 2007. A question asked about the tail feathers, the plane has been flown with and without the rounded ends on the elevators and rudder, I suggest using the rounded ends on the smaller tail version as it adds a bit of control area and seems to fly a little bit better. The rounded ends make it a little harder to cover. If your using the larger tail option you "may or may not" use the rounded ends on the elevators and rudder, building the PB-U or PB-1 with the standard size tail you can include the rounded ends on the elevator and rudder control surfaces. After trying both configurations the conclusion shows the rounded ends increases the control area and the aircraft seems to fly a bit better with the increased area. Note the rounded ends added to the Elevators in the pictures, they are not shown in the drawings. If you have built your Elevators and Rudder these are easily added after the fact even if they are added after the aircraft has flown. Suggested tube 5/16" or 3/8", use a bucket to bend around for general shape fasten with two rivets on each end where the hoop inserts into the tail tubes. This is not a safety bulletin but an update.

Dec 12, 2006. Please note that the USA 35B airfoil which is the design goal is quite a bit altered by the time you conform to the PBA building practices, look it over well to see how it will compare with the intended shape and alter your rib jig for the best overall rib shape.

July 2006, Suggest 8" wing rib spacing on all models (limits scalloping in the wing cover fabric).

Sept 15, 2005. Gear leg weakness, if you are using two tube gear leg with the pvc slider and need additional strength on the gear leg (bends during hard landings) you can build the gear leg assy. by removing the pvc slider and using an additional tube (1 1/8" tube). Make your assembly with a 3/4 x .058 6061 steel axel, 7/8 x .058 Al. tube, 1" x .058 Al. tube, and then a 1 1./8" x .058 Al. tube. This gives you a three tube gear, remember to use thin washers on the brackets for a bit of clearance and a little grease where the tube and brackets contact (slide) against each other, yes you'll get a bit of wear from the sliding contact but it will not be excessive and you will have a stronger gear assy. Be careful not to decide to make a superman gear (even stronger yet than this) as that may start to cause other components to fail when they are stressed, the gear tube legs are what is supposed to fail!

June 3, 2005, diagram DIA-WG-24, notice at the bottom of the strut brackets the drawing shows 1/8" holes, those are later drilled to 1/4" when fitting the struts, you can change the drawing to 1/4" in place of the 1/8" but the smaller hole is listed so that match drilling will correct any misalignment..

. From the back of the horizontal stabilizer to the support tube with the holes that adjust the horizontal stabilizers is 33"on center. 44 or 46" isn't critical but gee wizz I should get it right---- It looks like I should have had the arrow to the front edge of the vert stab instead of pointing to the horz stab support tube.

Mar 21, 2005: Note Diagram SE#13 Carry tube spacer dimensions are incorrect (should be 1" x 2" instead of 2" x 4").

Oct, 2003 When aligning or (bending the angle) on the main gear legs, set them so that the axels are straight out (level) when the gear is completely compressed (all the way down). When the gear is in the up position held by the bungee cords the wheels should be tipped out at the top (angled "in" at the bottom). Try the bend at 22 degrees, 25 degrees seems to be to much.. (pg.18)