Charlie Kuss wrote:
John Slade wrote:
I'm told that the 0-360 Lyc weighs in at around 310 not including prop
extension.
I weighed my '93 13B REW and accessories on a UPS scale as follows:
Engine less oil pan 178
Smog pump 7
Starter 8
water pump 10
Alternator 11.5
total 214.5
Add in the redrive at 35 lb, the mount plate at 5 and about 5 lb of water
and we come to about 260 lb for the 13B compared with the Lcy at 310. Of
course there will be other items like prop extension, oil and mount, but
these will be about the same on both. So, if we have a difference of around
50 lb, does this mean I should mount the 13B aft of the plans point for the
John,
Scanning your tally I want to know how much the radiator, it's hoses, mounting hardware, ducting, & header tank weigh? You've totally forgotten them. 5 pounds of water??? What am I missing here? Most automobiles have cooling systems of 2-3 gallons capacity to produce much LESS sustained power. You can save some weight by eliminating a heating system, since you live here in S. Florida, but you'd need that to fly north in the fall or winter. If you do include a heating system, add the weight of the heater and it's related hoses and hardware. How much oil will be in the PSRU??? What about PSRU & oil cooler hoses and hardware?
Paul,
Is 5 pounds for coolant really viable? 12-16 pounds seems a minimum realistic figure to me. I can tell you that the entire "cooling system" (baffles) on a Lycoming is only 3-4 pounds, including the seals. I'm not trying to abuse anyone, just trying to compare apples to apples.
Older Lycomings came with a Prestolite (now there's an oxymoron) starter which could double as a boat anchor. The newer units come with a permanent magnet starter which is half the weight. The "certified" alternators are also heavy. Most experimental builders substitute NipponDenso alternators to save weight. My point is that it is also possible to shave weight off the Lycoming's numbers. I suspect that these possible variables are why starters & alternators are not included in published weights.
Charlie Kuss
RV-8A hanging flaps & ailerons fuselage kit finally ordered
Boca Raton, Fl.
PS I saw Ed Anderson's oil pan in Ed Heishmann's shop yesterday. You're gonna love this thing when you get it back Ed. I hope to have photos of it within a week.
Water weighs eight pounds per gallon. The bottom line is the empty weights
of the aircraft are coming in at about the same weights as the Lycoming.
Right now we have a limited amount of data. Time will give us more
accurate numbers. For one thing as we learn how to build efficient
cooling ducting the weight of the rad and water should come down.
Paul Lamar
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