Curious how much weight the average person is able to shave off their plane when they switch over to primarily glass? Took a plane for a flight today that was at max weight. The current owner stated swapping to glass would save "a lot" of weight but I'm hesitant to believe that statement. He also has an old heavy battery in the plane that could likely be upgraded to a lighter one. There are a few other things that I can think of but the panel seems to be the biggest bang for weight in my opinion.
What equipment is installed now? Replacing the panel in my airplane with glass would probably save five pounds or so. Your mileage will vary. Ron Wanttaja
The biggest bang for weight is you and un needed gas. Weight savings depends on what equipment it has and what you put back in. Standard VFR panel to standard glass, maybe 10-15 pounds. Older IFR and auto pilot to new IFR and autopilot, up to 50lbs likely.
15# and 7.10 amps after removing the original 1960's era radio Narco MX12 (on a tray behind the bulkhead). I worry less about weight and more about power (amps). When I bought the cherokee, it had the original everything, but I added a belly strobe. Based on the original equipment and estimates where I couldn't find documentation, I had 46.45 amps with everything turned on (including the pitot heat for 5.0 amps). Single biggest improvement - replaced the landing light, rotating beacon (old Whelan), panel lights, tail light and wingtips with LED: 23.6 amp requirement became a mere 7.27 amps (the belly strobe still takes 3.2 amps - that changes next summer at annual) Not sure about the weight change for avionics, but the required amps definitely change. Replaced the old Narco radio and encoder & transponder. The DME is flakey, and as much as I like it, something else that goes away next summer (another 2 amps, too). Best estimate is Original: 46.45 Now: 22.75 amps
Thanks all, this was my suspicion as well. The plane has a minimal vfr panel at best. Steam gauges (no vacuum gauges). A few engine monitoring gauges and the smallest form factor radio I've ever seen. The plane was nice as a potential purchase candidate, but it was built heavy and while flying it was concerning as it was either out of rig, overweight, or both.
There may be many other ways to shave off weight. Convert 25 lb lead acid battery to 4 lb EarthX, remove wheel fairings, remove interior carpeting/panels/seats and replace with lighter weight. If the engine is Lyco or Conti, install light weight starter, light weight alternator, lighter weight prop. All these things are "relatively" cheap when compared to making these changes on a certificated plane. Care to share the type of plane?
Fully primed interior, multiple coats of paint, lots of sound insulation, leather seats, upholstery covering every square inch of floor, sides and ceiling, standard starter, alternator, and battery.
FYI: sometimes various installed equipment like batteries are used to keep the aircraft within its empty wt CG. So before actually removing/replacing various items to save weight recalculate the anticipated new empty and most forward/most aft CGs. Nothing ruins a day more than gaining 30 lbs of useful load only to add 15 lbs of lead back to keep the aircraft flying straight.
Upholstery, insulation, and old/heavy accessories can be fixed with a few bucks and a couple of weekends of sweat equity.
For many (most?) of us, the best place to lower takeoff weight is from the abdomen, thighs and buttocks. For avionics, if you can lose the vacuum system, that is usually where a big chunk of weight comes out, dropping the pump, DG, AI, suction gauge and tubing. If you go all-in, you could drop the ASI, VSI, CDIs, altimeter and engine gauge cluster too, and combine it all into three multi-function units (1 primary, 1 backup/HSI-type, one engine monitor). Your wallet will be a lot lighter too.
"Well, thar's yer problem....." Can you give us an idea of book empty weight vs. current empty weight? Stock empty weight for a Fly Baby is 605 pounds, the builder of mine added 200 pounds in various ways. Metal areas that were supposed to be 0.016" aluminum used 0.040", replaced 0.016" leading edges with fiberglass, fiberglass upholstered seat instead of a 1/4" plywood, big 'ol Narco radio, larger engine with full electrical and cockpit heat. I've added a transponder, ADS-B out, bigger tires, and a power lift seat (bad knees). Got it lighter by replacing the stock battery with a dry cell, and the Delco alternator with a B&C. Haven't re-weighed it, but figure it's 10-15 pounds lighter. Actually, ten years or so ago, I was contemplating installing a Dynon in my Fly Baby...more for the amusement than anything else. Did a layout, and it would just barely fit in the removable center-section of the panel.... Three issues prevented me. First, it would have displaced the radio, and I didn't have any remaining panel space for it. Second, depth was an issue...the fuel tank is located fairly close behind the panel. Third, I wasn't sure of the Dynon's readability in sunlight (open cockpit). Ron Wanttaja
It's a dragonfly Mark iii. Not much interior to remove but the battery could help. Before looking at the plane I was thinking the starter would get swapped for a lighter weight one. Upgraded avionics in my brain would gain me maybe 15 pounds. Wheel fairings are possible as its got them and I'm not sure how heavy they are. Sad thing is I was seriously considering this plane before I went to look at it and the flight is what turned me off. It needs other work to work for me as well but the heavy build is its biggest issue. Seller just confirmed with me that he thinks we could shave 20-25 pounds off the plane with some updates but nowhere near what I would like to shave off of it to make it work for me.
No vacuum system in this plane. Current instruments are airspeed, altimeter, vsi, rpm, old transponder, a pair of cht/egt guages, volt/amp guage, fuel tank guage, oil pressure/temp guage, and radio that fits into a 3 inch hole on the panel. If I bought it this would be my list of things to lighten my wallet and improve its usefulness for me. -install dual G5's or something similar -replace the transponder and radio with a nav/com/gps/transponder all in one unit. -replace the starter with a lightweight one -replace the tach and engine guages with some sort of engine monitor that covers all the gauges removed. -replace the battery and possibly move it to a better location for Cg *prop is a ground adjustable prop so it acts like a fixed pitch prop- if a lighter version is available I'd consider it but that would take some research. -seat cushions and interior panels are good but minimal so I'm not sure much weight would be saved there. *Wheel fairings could come off to save weight but even with all the above mods I'm still hesitant to believe it would get to what I would need. There are other mods I'd consider but none that affect W&B.
