KingCat ADs

Installing the 12X in a BVM KingCat
(03/20/2008)

Large Fuel Cell Transfer Tubes
Replace Brass with Stainless Steel
(4/20/06)

There has been one case where the brass tube that transfers fuel through a hole in the fuel cell baffle experienced a razor saw-like cut. The engine flamed out because the remaining fuel below the tube was unusable.
The most likely cause of the brass tubing failure was many miles of trailer transport of the model with the fuel cells empty.

The Fix

BVM now supplies Stainless Steel tubes with the large baffled fuel cells i.e., KingCat, F-100, F-4, Rafale, F-86 (80"). Retrofit parts are available. Ask for part #PSTU003 (quantity 2) price $5.00 for the pair mailed within the USA.
To be honest, we don't know how many travel miles the brass tubes will withstand. It could vary quite a bit. BVM is converting our factory demo models as time allows. Our prototype F-100D is 6 years old, has at least 300 flights and more trailer miles than we can count. We inspected the brass tubes and found minimum wear. We changed them to the Stainless Steel variety anyway.

KingCat Instruction Update - BOOM ASSEMBLY ADDENDUM
(2/2/06)

click here to download the update (pdf file)

KingCat Instruction Update (page 19)
(12/22/05)

click here to download the updated page 19 (pdf file)

KingCat Boom Reinforcement
(9/17/04)

There are at least 200 KingCats actively flying now and enduring the stresses of high speed flight, High-G maneuvering and less than perfect landings.
There have been problems recently with the booms on two aircraft. As explained in the previous A.D. (July '04), these semi-monocoque structures rely on the integrity of the glass/foam/glass laminate for strength. If the lamination is damaged, i.e. delaminated for any reason (even excessive squeezing during model assembly), there can be a soft spot in the boom structure.
This .020" carbon fiber boom reinforcement kit is offered to all KingCat customers at no charge for the parts and instructions. There will be no shipping charge for USA customers. Shipping outside the USA will be whatever is most economical.
If you have been flying your KingCat a lot and have confidence in the integrity of its boom structure, you may be satisfied with it the way it is.
If you have any concerns about them (booms), we highly recommend installing this reinforcement kit. It takes less than an hour and some SLO-ZAP to accomplish.
The thin machined reinforcement strips have a shiny carbon fiber weave surface similar to that used to decorate custom automotive interior panels. The aerodynamic shape of the side panels is also attractive and should not need any touch-up painting.
Boom reinforcement kits and very detailed installation instructions will become available to be shipped the week of September 20th, 2004.
Due to the numbers involved, it will take us about 4 weeks to supply all KingCat owners. New kits are being shipped with the reinforcement kit factory installed as of September 20, 2004.

Contact BVM at 407-327-6333 (tel) or 407-327-5020 (fax).

KingCat Strut Screws
(8/4/04)

The 2-56 button head screws that retain the "slider pin" in each strut should be checked for security. If any of them are easy to remove, they should be treated with a Thread Locker.
Use Pacer Z-42 (shake before use) (click here) and apply one small drop to each screw and reinstall with a 1/16" hex wrench. Check strut oleo action after 1/2 hour of cure time.
It is best to just snug the screws rather than overtighten them.

NOTE: If one or more of the screws is difficult to remove from the slider pin, leave it as is.

KingCat Flap Servo Screws
(8/4/04)

Some high flight time KingCat pilots have found that the screws that retain the flap servo mounting brackets to the 1/4" plywood platform have worked loose after a fair amount of flights.

The Fix

Remove the flap servos, apply a drop of C.A. to the servo holes and allow to kick. Then reinstall the screws and check that they will snug up.

KingCat Flap Extensions
(7/27/04)

The RF Filters have been removed from the flap servo extensions, thus eliminating the 6" extensions used and any chatter that was occurring in the servos.

KingCat Booms
(9/26/04)

Bouncing transport, mishandling or rough landings may cause damage.

Fix Before Flight

The KingCat boom/fin components are a fiberglass/foam/fiberglass laminate that are cured in the molds under a vacuum. The internal structure is glued into one half and then the two halves are joined while still in the molds.
This semi-monocoque construction produces a light, yet strong structure that relies on the integrity of the bonded materials in the laminate for strength.
It is possible to cause delamination through pinching or extreme flexing such as in a very hard landing; especially one involving a side load.
There has even been one model damaged by severe bouncing loads from being transported in the back end of a trailer. During this type of transport, it is recommended that all models be evenly supported on thick foam rubber.

How to inspect for damage:

If delamination has occurred, the outer fiberglass skin will be detached from the foam and obvious to the eye and touch. Check also to see if there is a split in the fore/aft mold join line top and bottom.

How to fix:

Use a Perma-Grit burr (#RF6C) in a Dremel tool to make some holes through the outer skin and just into the foam laminate.
Apply thin C.A. in holes allowing it to seep between the F/G skin and foam. Use food wrap to protect and gently press the laminate together while the C.A. cures. NOTE: C.A. will not attack this type of foam.
Fill the holes with F/G putty and trim flush.
Make a skin patch from .010" poly ply (BVM #5710). Scuff both sides of the patch and the surface of the boom with #400 sand paper.
Apply Slow C.A. to the back side of the patch (avoid the edges to allow it to spread out) then apply to boom and hold for cure.

Curved surface repair:

Tape off a rectangular area around the tear, scuff with #220 grit then apply a patch of 4oz fiberglass and epoxy resin. Sand after cure and brush prime.

Color Paint

BVM sells one ounce bottles of the KingCat colors and the appropriate hardener. Use PPG DT reducer to thin and airbrush the repair.
See also skin patch tips (click here).
NOTE: For badly damaged booms from a tumbled landing, it is necessary to replace these parts completely.

Call for pricing

Rudder and Elevator Servo Covers

To utilize the socket head servo screws supplied with your KingCat, it is necessary to make small clearance holes for the aft two screws in the cover plates.

NOTE: Early kits will require that the nose wheel clearance opening be enlarged per this drawing. Note that the Smooth stop valve is shimmed 1/4" above the board.

JetCat I/O board is mounted with (2) angle brackets (BVM #MC5090). ECU board is painted grey and shown with all components mounted and ready to install into fuse.

Airframe Directive's

The following drawings should help to clarify the placement of the control horns.

The dimensions on the original plans do not change, these drawings emphasize that the fore/aft location of the horns is determined by the L.E. of the horn base - the part that is buried into the control surface.

NOTE: Slots in the control surfaces may vary a bit, adjust them as necessary.