---------------------------------------------------------- Seaplane-List Digest Archive --- Total Messages Posted Mon 03/12/07: 2 ---------------------------------------------------------- Today's Message Index: ---------------------- 1. 09:16 AM - float rigging (Peter C) 2. 11:29 AM - Re: float rigging (Noel Loveys) ________________________________ Message 1 _____________________________________ Time: 09:16:19 AM PST US From: "Peter C" Subject: Seaplane-List: float rigging Is anyone aware of any significant document that goes into detail on the various aspects of hanging floats on an aircraft? I've heard the assorted rules of thumb about step placement and angle and have successfully mounted floats before but I'm curious about what is behind some of the ideas and the affects of deviating from them. For example one formula says mount the step 1/4 (or 1/3) of the WIDTH of the float behind the cg. Where does this come from? How does float width affect this? Another says mount the step so as to intersect a line drawn 6 degrees aft of the cg. This imples that height of the rigging affects step placement. What are the factors affecting height above the floats? Why is loading never mentioned? In other words wouldn't the step position be of more interest to the cg at gross than empty cg? Surely there is a reference book on this somewhere. I was not successful with google searches. Thanks Peter ________________________________ Message 2 _____________________________________ Time: 11:29:29 AM PST US From: "Noel Loveys" Subject: RE: Seaplane-List: float rigging the recipe I use for locating the installation point for floats is: *Obtain one float *Obtain a small body of water . *Put the float in the body of water. *Start filling the front compartment of the float and continue until the float floats level. *Remove the float from the body of water. Now it gets tricky *Obtain a stick about two feet long and 4'-10' in diameter ( about the size of a nice stove billet ) *Rest the float on the stick so the stick supports the keel of the float and roll it ahead until the float is balanced. *Measure the distance back from the front of the float the stick is. *drain the water out of the float. *Mount the floats so the CG of the plane is the same distance back from the front of the floats as the measurement tow steps ago. Install the float so the AOA of the plane is about 1-3deg up. No mixing required No oven stove or refrigerator Also no ballast required to get the plane up on step. Weakness of recipe: For planes that are tandem seating the overloading of the back seat will cause the tails of the floats to sink. For such planes put the CG over the balance point of the floats when the plane has a medium load...with the landing gear removed. The whole idea is to get the plane to float more or less level at rest in the water. There are some who intentionally float planes like the super cub with too much weight forward. These planes require carrying ballast in the back seat to enable the plane to get up on step. They also enable the plane to carry a whopping big load behind the pilot. Noel -----Original Message----- From: owner-seaplane-list-server@matronics.com [mailto:owner-seaplane-list-server@matronics.com] On Behalf Of Peter C Sent: Monday, March 12, 2007 1:46 PM Subject: Seaplane-List: float rigging Is anyone aware of any significant document that goes into detail on the various aspects of hanging floats on an aircraft? I've heard the assorted rules of thumb about step placement and angle and have successfully mounted floats before but I'm curious about what is behind some of the ideas and the affects of deviating from them. For example one formula says mount the step 1/4 (or 1/3) of the WIDTH of the float behind the cg. Where does this come from? How does float width affect this? Another says mount the step so as to intersect a line drawn 6 degrees aft of the cg. This imples that height of the rigging affects step placement. What are the factors affecting height above the floats? Why is loading never mentioned? In other words wouldn't the step position be of more interest to the cg at gross than empty cg? Surely there is a reference book on this somewhere. I was not successful with google searches. Thanks Peter ------------------------------------------------------------------------------------- Other Matronics Email List Services ------------------------------------------------------------------------------------- Post A New Message seaplane-list@matronics.com UN/SUBSCRIBE http://www.matronics.com/subscription List FAQ http://www.matronics.com/FAQ/Seaplane-List.htm Web Forum Interface To Lists http://forums.matronics.com Matronics List Wiki http://wiki.matronics.com Full Archive Search Engine http://www.matronics.com/search 7-Day List Browse http://www.matronics.com/browse/seaplane-list Browse Digests http://www.matronics.com/digest/seaplane-list Browse Other Lists http://www.matronics.com/browse Live Online Chat! http://www.matronics.com/chat Archive Downloading http://www.matronics.com/archives Photo Share http://www.matronics.com/photoshare Other Email Lists http://www.matronics.com/emaillists Contributions http://www.matronics.com/contribution ------------------------------------------------------------------------------------- These Email List Services are sponsored solely by Matronics and through the generous Contributions of its members.