Shared Tri-Champ numbers.

Boundary Waters

Pre-takeoff checklist
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Sep 24, 2021
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Luscombe Driver
Obviously, I am really into the physics of how we become like birds for a (too) short time.

This Equipment List and Weight and Balance were shared by a Tri-Champ owner (who interestingly bought his airplane to convert it to a 7EC, but then decided not to, he thus remains anonymous.)

"The Mother of all Equipment Lists" begins with some estimates based on the last actual weighing of the airplane (2006).

EQUIPMENT LIST

457 lb: ESTIMATED: Empty weight of uncovered airframe, control cables, etc.

12 lb unusable fuel at unknown arm. Calculated arm below includes unusable fuel and cover.

+48lb ESTIMATED: Poly-Fiber Finishing System, vs 78 lb original weight of cotton and dope.

517 (+31.46) +16267

162 lb --36 (--5832) ESTIMATED: Continental C-90-12F without carb, manifolds, or accessories.

679 --5832 +10435

+9 at --30 (--270) Marvel-Schebler Carburetor 10-4457-1 and manifold

688 --270 +10165

+14 at --26 (--364) Item magnetos, two, with eight shielded wires, and eight resistor plugs.

702 --364 +9801

+1 at --6 (--6) Item: Main Electrical Switch

703 --6 +9795

+0.5 at --6 (--3) Item: Electrical Switches

703.5 --3 +9792

0.5 at --6 (--3) Item: Fuses and Panel

704 --3 +9789

+3 at --4 (--12) Item: Intercom

707 --12 +9777

+2 at +5 (+10) Item: Throttle and Linkage

709 +10 +9787

+0.5 at --6 (--3) Item: Exhaust Gas Temperature Gauge

709.5 --3 +9784

+1.5 at --6 (--9) Item: Altimeter 1.5 lb (-6)

711 --9 +9775

+1 at --6 (--6) Item: Airspeed Indicator 1 lb (-6)

712 --6 +9769

+1 at --6 (--6) Item: Magnetic compass 1 lb (-6)

713 --6 +9763

+2 at --6 (--12) Item: Tachometer 2 lb (-6)

715 --12 +9759

+0.5 at --6 (--3) Item: Oil Temperature Gauge 0.5 lb (-6)

715.5 --3 +9753

+0.5 at --6 (--3) Item: Oil Pressure Gauge 0.5 lb (-6)

716 --3 +9750

+21 at --54 (--1134) Item 6: Propeller, McCauley 1B90 ST 7152: 21 lb. (-54)

737 --1134 +8616

+1 at --57 (--57) Item 4(a): Spinner (Aeronca dwg. 4-710 and 4-711) Model 7FC 1 lb. (-57)

738 --57 +8561

+2 at --47 (--94) Item 102(b): Carb air scoop (Champ dwg. 4-877-3 or dwg. 4-877-4) 2 lb. (-47)

740 --94 +8467

+1 at --47 (--47) Item 103(b): Carburetor Air Filter (Aeronca Dwg. 2-849) 1 lb. (-47)

741 --47 +8420

+13 at --42 (--546) Item 105: Hanlon and Wilson mufflers and heaters 13 lb. (-42)

754 --546 +7874

+4 at --26 (--104) Item 108: Oil filter - Fram PB-5, Kit No. 510, Includes 1 qt. of oil. 4lb (-26)

758 --104 +7770

+16 at --28 (--448) Item 111 Starters (a) Delco-Remy No. 1109656, 12V, Model 7FC 16 lb. (-28)

774 --448 +8218

+1 lb at --5 (--5) Item 117(a) Mixture Control installation (a) (Champ dwg. 4-1013) 1 lb. (-5)

775 --5 +8213

+48 at +26 (+1248) Item 201(f) Goodrich wheel and brake instln. 8.00-6, 4-ply tires 48 lb. (+26)

823 +1248 +10461

+13 at +26 (+338) Item 201(e) 4-1139 axle assembly permits 1500 GW 13 lb. (+26)

836 +338 +10799

+1 at --8 (--8) Item 207(b) Parking brake Model 7FC (Champion dwg. 4-1023) 1 lb. (-8)

837 --8 +10807

+9 at --31 (--279) Item 209 Nose 5.00-5 Cleveland wheel and Type III, 4-ply tires 9 lb. (-31)

846 --279 +10528

+3 lb at +10 (+30) Item 210 Hydraulic brake installation (b) Scott hydraulic brake 3 lb. (+10)

849 +30 +10558

+2 lb at +24 (+48) Item 305(a) Lights and harness, 2 lb. (+24)

851 +48 +10610

+2 lb at +20 (+40) Item 305(b) Position lights and harness, 2 lb. (+20)

853 +40 +10650

+1 lb at +90 (+90) Item 305(d) Position lights and harness, 1lb. (+90)

854 +90 +10740

+22 lb at --27 (--594) Item 307 Battery (d) Exide AC-54 manifold vented, 22 lb. (-27)

876 --594 +10146

+16 lb at --28 (--448) Item 308(a) Generator, voltage regulator, Delco-Remy, 11 lb. (-28)

892 --448 +9698

+2 lb at +4 (+8) Item 310(d) Landing light (dwg. 4-1001) Model 7FC 2 lb. (+4)

894 +8 +9707

+13 lb at --8 (--104) Item 312(a) Radio Equipment, Narco VHT-3 Superhomer 13 lb. (-8)

907 --104 +9603

+1 lb at +13 (+13) Item 312 (Champ dwg. 7-1167) Cabin speaker instln. (optional) 1 lb. (+13)

908 +13 +9616

+2 lb at +18 (+36) Item 313 Rotating beacon (a) (Champion dwg. 4-1020) 2 lb. (+18 0)

910 +36 +9648

+14 lb at +17 (+238) Item 401(a) Adjustable front seat cushion and belt (a) 14 lb. (+17)

924 +238 +9886

+18 lb at +46 (+828) Item 404 Seats (a) Wide rear seat, cushions and belt, 18 lb (+46)

942 +828 +10714

+5 lb at +10 (+50) Item 405 Soundproofing (side panels, headlining and firewall) 5 lb. (+10)

942 +50 +10714

+15 lb at +28 (+420) Item 406 Interior (upholstery, floor mat, bag cmpt and lid) 15 lb. (+28)

957 +420 +11134

+7 lb at +20 (+140) Item 407(b) Fire extinguisher (Champ instln. dwg. 7-10004) 7 lb. (+20)

964 +140 +12274

+3 lb at +68 (+204) Item 409(d) ELT, Ameri-King AK-450 (Champ dwg. 3-1689) 3 lb (+68)

967 +204 +12478< -- empty CG (incl 2.0 gal fuel and 1.0 qt oil) is at +12.9

Changes noted at purchase

--7 lb at --8 (+56) New radios at Item 312(a)

+1 lb at +90 (+90) ADS-B added to Item 305(d)

--3 lb at +20 (--60) New fire extinguisher at Item 407

--1 lb at +68 (--68) New ELT at Item 409

--10 lb (+38)

957 (+13.07) +12514 < -- new calculated empty CG


Unchanged W&B _____Updated W&B

967 (+12.9) +12474 _____957 (+13.07) +12514 < -- CG okay, empty

9 --35 --315 < --- Oil (one quart in filter included in empty weight)

170 +11.5 +1955 < --- Pilot (using CAR 3 standard, actual weight is 158 lb.)

1146 (+12.32) +14114 _____1136 (+12.46) +14154 < -- CG okay, oil and pilot

144 +24.0 +3456 < --- 24 gal. usable, 26 gal. system, 2 gal. included in empty weight.

1290 (+13.62) +17570 _____1280 (+13.76) +17610 < -- CG okay, oil, fuel, and pilot

170 +42.0 +7140 < --- Can carry 183 pounds instead of passenger and rear seat

50 +64.0 +320 < --- Maximum normal baggage

1510 (+16.58) +25030 _____1500 (+16.71) +25070 < -- CG okay, full load

From A-759:
C.G. range at 1500 lb. is as follows: (+15.0) to (+18.5) at 1500 lb.

(+10.2) to (+18.5) at 1190 lb. or less Straight line variation between points given.

No. of Seats 2 (1 at +11.5, 1 at +42).

Maximum Baggage 50 lbs. at +64.

Fuel Capacity 26 gal. (two 13 gal. wing tanks +24)

Oil Capacity 5 qt. at -35.
 
"The Mother of all Equipment Lists" begins with some estimates based on the last actual weighing of the airplane (2006).
Without a scan of the last actual Empty WT & BAL sheet your list loses its context. And does the current computed empty W&B figures with the estimated weight items include a certifying signature as well?
 
Without a scan of the last actual Empty WT & BAL sheet your list loses its context. And does the current computed empty W&B figures with the estimated weight items include a certifying signature as well?

The file was sent to me digitally, and either it didn't translate well, or I don't know how to properly import it... The last (2006) ACTUAL empty weight was 957 lb at +13.07 and the first few entries are estimates after backing out the +/-300 items on the equipment list. My best guess is that many of those are estimates or approximations. But the errors likely offset one another through so many entries.
 
But the errors likely offset one another through so many entries.
FYI: as long as the estimates were part of the EL prior to the actual WT&B no issues. But if the estimates were used for the calculated EWB then issues. And the last place you want "errors" is with the certified EWB on several levels.
 
An actual (I presume certified) weight was taken in 2006 and the W&B is based on same.

Contrary to* "internet fact" the airplane gained 10 pounds of useful load at that weight (newer electronics and fire extinguishers are lighter than older ones) and it gained 23 pounds at a previous weighing (Poly Flight being lighter than Grade A Cotton and dope).

The plane weighs what it weighs, but the equipment list is based on the TCDS which uses estimates / rounded weights. Any list of estimates, it the estimator has no agenda, will tend to balance over time with the errors / rounding to the left equaling the errors / rounding to the right.

*Grrr... spell changer (not spell checker)
 
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but the equipment list is based on the TCDS
Not quite. The aircraft Equipment List is based on the configuration of the aircraft at the time of actual weighing. It has zero to do with the options listed in the older Aircraft Specifications Sheets or the later TCDS. Two separate rules. Do both listing cross over, yes. But not at the same time.
So trying to rebuild an Equipment List one would contact the original OEM for a copy of the original EL, if applicable, or would use the existing configuration of the aircraft. You’re starting to miss the trees from the forest again. Once an aircraft is actually weighed the individual weights and arms of the installed equipment become moot as the proper way to remove said equipment is weigh/measure location of the equipment at that time and compute the new EWB. If a proper removal weight and arm can not be determined, the corrective action is to reweigh the aircraft.
 
Removing 13 pounds of radios and replacing them with seven pounds moves the CG a tenth of an inch. In the real world all sorts of minor differences are moot. This is more an "quasi-scientific" inquiry than anything. I get that legally once the aircraft has a legal reweigh that none of the original numbers in the TCDS mean anything. But nobody disassembles a working airplane to weigh the pieces. And ounces make pounds.

1500 pounds gross weight
340+144+50+9=543 pounds of people, gas, bags, and oil.
957 pounds of airplane including 26 pounds of instruments, radios, and lights... a 54 pound electrical system... 74 pounds of landing gear... and 52 pounds of upholstery.
Pulled along by a 162 pound engine with 55 pounds of accessories... A 21 (or 23.5) pound propeller...
450+ pounds of wood spars, steel tube, multistrand cables, aluminum sheet, pulleys, plexiglass, and plywood kept aloft by 48 pounds of polyester fabric and paint...

I find it fascinating to think of the individual parts which make up the whole...
 
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This is more an "quasi-scientific" inquiry than anything.
I find it fascinating to think of the individual parts which make up the whole...
The only people I know that share your obsession are aircraft designers/engineers. Are you an engineer by chance? Regardless, most weight-reduction exercises with production aircraft usually end up in one of 2 places, an aircraft so basic no one wants to fly it, or the 13.20498475 lbs you remove to save weight ends up requiring a 10.18472849 lb chunk of lead mounted somewhere on the airframe to make the aircraft fly straight. Why not apply your talents to something more practical like design/build a Luscombe or Champ replica out of carbon fiber/Oratex or some other light materials? Then you could really take your weight saving premise to the nth degree.
But nobody disassembles a working airplane to weigh the pieces.
Some people do when flying unique ops, or attempting world records, or racing. Been there, done that, on the unique ops route. Never say never.;)
 
It looks like Current Production Luscombes are built as per legacy.

Would be a thought though.

My guess there are others like Porterfields and Interstates that have the Type Cert

for sale reasonably.
 
The only people I know that share your obsession are aircraft designers/engineers. Are you an engineer by chance?
Professionally, yes.
Regardless, most weight-reduction exercises with production aircraft usually end up in one of 2 places, an aircraft so basic no one wants to fly it,
For myself, flight in itself is a goal, so my requirements so far as luxury is concerned are minimal. I know I am in the minority. But I also think that many who love antiques and a good part of the Part 103 crowd looks at the equation similarly. I'm not there because I think that 103's restrictions compromise safety.
or the 13.20498475 lbs you remove to save weight ends up requiring a 10.18472849 lb chunk of lead mounted somewhere on the airframe to make the aircraft fly straight.
Ah, but the goal isn't to be lighter than air. The trick is to remove everything that isn't necessary so you have a "pure" flying experience. And you never add unnecessary pounds. A great many things don't care where they are sitting on the airframe, move them. A longer motor mount hardly weights any more than a shorter one. I know many float plane pilots that moved stuff to balance better-- either exclusively on floats or to facilitate switching back and forth.

Computer programmers make programs that duplicate modern aircraft where the pilot doesn't fly the airplane. The pilot flies the computer that flies the airplane. And with a game you can hit reset if the computer has a glitch and decides to fly you and 236 others out into the middle of the Indian Ocean. But what fun is that?
Why not apply your talents to something more practical like design/build a Luscombe or Champ replica out of carbon fiber/Oratex or some other light materials? Then you could really take your weight saving premise to the nth degree.
Long term, that is similar to my goals, the earliest Taylor E-2 was a parasol that hardly weighed any more than a Heath. 4130 effectively weights the same as 1025, functionally it weights less. Pulling a wooden propeller through gives you a read on compression and starting it by hand gives a sense of accomplishment. Otherwise, you might as well just flip the switch and watch the landing gear position lights on a Champion Lancer...
 
It looks like Current Production Luscombes are built as per legacy.

Would be a thought though.

My guess there are others like Porterfields and Interstates that have the Type Cert

for sale reasonably.

I saw an 8-SLSA in Arkansas over the weekend. Gorgeous. 30 gallon fuel system, O-200, light weight electrics, composite Sensenich ground adjustable prop. (If you have to ask you can't afford it, but not nearly as much as a new Cessna. But I'm going to stick with used classics 'till I build one myself.)
 
Buy a wingsuit. Can't get purer than that.
"Excuse me, Izod?"

"No, Rocket J. Squirrel..."

There are a few Problems with that idea.
(1) I don't trust seams sewn by indentured servants in third-world sweatshops.
(2) They probably (honestly, I never asked) have a rule against jumping from the observation level of the Enger Tower.
(3a) I'm uncertain of the glide slope of a flying squirrel suit but Sky Harbor is eight miles or so SE of the tower...
(3b) DYT is at 608 feet AMSL so that's 532 feet lower than the tower...
(3c) Even with a ten knot wind it probably means I'm gong to come down in the harbor...
(4) Pursuant to (3c) the water is 58 degrees Fahrenheit.
(5) The Lake Avenue bridge is closer than walking eight miles back through the city to jump again, but it's only 135 feet tall.
(6) Probably won't make it to DYT... But if I did, it would be fun explaining the suit to the OI when I landed...

I'll keep the airplane.
 
I don't trust seams sewn by indentured servants in third-world sweatshops.
Picky, picky. Well then how about a glider or motorized glider for the purer side of aviation? Seems that's what your end game is on the Luscombe, to strip it down to nothing. Or maybe a balloon?
 
Picky, picky. Well then how about a glider or motorized glider for the purer side of aviation? Seems that's what your end game is on the Luscombe, to strip it down to nothing. Or maybe a balloon?
Not strip it to nothing. Just nothing extraneous. And I don't have to strip it really. Back when it was built they didn't glop all the latest fads (like radios, instruments, and starters) on airplanes. Rubber mats are more functional than carpeting, especially in snowy places. People invested in VORs, now they are going away... Just wasted money :).

I can fill the seats and the baggage compartment and the fuel tank and have a blast. (Admittedly it's only a 14 gallon fuel tank... But it also burns a mere four or so gallons an hour). We did eight states in six days over the three day weekend...

Little two place 65 hp airplanes are pretty much "motorized gliders." I have a big long graceful wing that provides plenty of lift at low speeds. In fact the Taylorcraft that I learned to fly in was built as a Army Air Corps training glider and had an engine mounted post-war. Piper and Aeronca built training gliders based on their two place tandems as well.
 
Six days into three? Pretty neat trick! ;)
Harry Chapin once said that he spent a whole week in Watertown, New York one afternoon (in the lead up to the song 'A Better Place to Be').
 
Or John Denver's song "Saturday Nite in Toledo, Ohio" with the line "I spent a week there one day..."
 
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