Basic empty weight

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Basic empty weight

Postby Wyoming1 » Fri May 26, 2023 4:35 am

Curious as to what your showing for a basic empty weight? And is that an actual certified weighed weight or calculated from factory?
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Re: Basic empty weight

Postby voorheesh » Fri May 26, 2023 8:04 am

Empty weight (Licensed) is airframe, engine(s), items of installed equipment, unusable fuel, hydraulic fluids, and engine oil that cannot be drained.

Standard empty weight is the above but with the engine oil added. This value should be entered in the airplane weight and balance record at the time of manufacture.

Operators, owners, pilots can find this information in the W&B record required to be carried aboard.

As an airplane ages and is maintained and/or modified, the owner is required to update the record to ensure it properly shows the current empty weight and CG location. Changes of less than one pound (rivits, nuts, bolts, washers, etc) are considered negligible and do not require calculation. Changes of more than one pound require calculation per station location and must be documented by a certificated maintenance technician or repair station. (Some might argue that statement). In any case this results in a revised W&B record.

When contemplating the empty weight of a seventy year old airplane, a good place to start is the equipment list which can be compared to the actual configuration and weight and balance record(s). If there are significant discrepancies or missing documentation, the airplane can fairly easily be reweighed and a revised (current) empty weight and CG location established.
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Re: Basic empty weight

Postby Wyoming1 » Fri May 26, 2023 6:10 pm

Understood. Just interested in what other 170 owners have as their BEW.
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Re: Basic empty weight

Postby rnealon1 » Fri May 26, 2023 7:37 pm

I had my '54 170B with stock C-145 engine and no major modifications weighed a few years ago:

BEW: 1330 pounds
CG: 39.70"

This was within 14 pounds and 1" of the calculated BEW and CG, based on the original Licensed Empty Weight.

Bob
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Re: Basic empty weight

Postby voorheesh » Sat May 27, 2023 6:21 pm

Wyoming1 wrote:Understood. Just interested in what other 170 owners have as their BEW.


Sorry! Misunderstood your question. I’m a CFI and have a student who needs explanation for basic weight, etc. and your post gave me chance to practice a lesson.

I used to own a 1950 170A that had all its original records including weight at manufacture. It went through numerous modifications including adding floats, Horton STOL, and others. When I reweighed it (back on wheels), it was just under a 100 pounds heavier than original. About 50 years old at the time. Everyone of these old airplanes likely has their own story and in my experience most gain weight over the years.
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Re: Basic empty weight

Postby redacted » Sat May 27, 2023 11:36 pm

Mine on 8.50's is 1420. On 29's it's 1444.

Lyc O-360 Avcon conversion, MT prop. 175 wings, sportsman cuff, AK bushwheels tailwheel. Def some pounds added on, I think the sportsman kit is 20#
Nathaniel Perlman
1952 170B
N2282D S/N 20434
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Re: Basic empty weight

Postby ghostflyer » Sun May 28, 2023 12:30 am

While I will admit this is a bit of a thread drift but when have we checked our Take off/landing check sheets etc for accuracy. I was talking to some colleagues and they were surprised at my speeds for landing and other Manouvers. All my speeds were 10 kts faster or totally wrong . This information was printed on the check sheet that was in the aircraft when I purchased the project. While it was old and tattered it had 170 series and 172 series up to the D series on the top of the sheet . After getting some heat from my “friends” I then asked Gahorn[George] what speeds he used . For 2 hours i practised circuits and his suggestions and wow, from trying to put down a crazy tiger it’s now a pussy cat to land . My landing runs are 50% shorter . Thank you George .
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Re: Basic empty weight

Postby Wyoming1 » Fri Jun 02, 2023 2:46 pm

redacted wrote:Mine on 8.50's is 1420. On 29's it's 1444.

Lyc O-360 Avcon conversion, MT prop. 175 wings, sportsman cuff, AK bushwheels tailwheel. Def some pounds added on, I think the sportsman kit is 20#


This is interesting to me. I have the same engine conversion (170A model), Hartzell prop, standard wings and wheels and am at 1270#. I took the back seat out and dropped another 31# putting me at 1239#. Which MT prop did you put on? That is definitely on my wish list as are the 8.50's.

Thanks for the input.
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Re: Basic empty weight

Postby Joe Moilanen » Fri Jun 02, 2023 4:51 pm

Wyoming1 wrote:
redacted wrote:Mine on 8.50's is 1420. On 29's it's 1444.

Lyc O-360 Avcon conversion, MT prop. 175 wings, sportsman cuff, AK bushwheels tailwheel. Def some pounds added on, I think the sportsman kit is 20#


This is interesting to me. I have the same engine conversion (170A model), Hartzell prop, standard wings and wheels and am at 1270#. I took the back seat out and dropped another 31# putting me at 1239#. Which MT prop did you put on? That is definitely on my wish list as are the 8.50's.

Thanks for the input.

For what it's worth, I have an uneasy feeling about MT props. I'm not here to put them down, just thought I'd relate a story of something I that happened last year. I flew into Johnson Crk., Idaho (popular back country strip in Idaho)in August. apparently a week before I arrived two twin Brothers and their dog departed the strip in the morning in their Husky (with an MT prop). At about 650' AGL and just past the end of the runway they apparently lost propulsion and tried the "turn back" with the unfortunate "stall-spin" results. The Husky went straight down, nose first into the rocky creek. Only the dog survived. The caretaker of the strip found the spinner, hardly damaged along the bank of the creek. I looked at Flightaware and it looks like the location of the spinner and and where the Husky quit climbing were about the same. The prop hub had one blade sheared at the hub and the other blade was totally missing... The caretaker brought the spinner to the attention of the NTSB while they were there but they didn't seen to interested so he put it in the back seat of their vehicle. A couple of days later the caretaker went back to the scene and found the spinner laying on the bank...maybe it's easier to write an accident off as "stall/spin/pilot error" than to spend time investigating it?? I truly believe the Husky pitched a blade on climb out. I spent an entire day combing the surrounding woods looking for the blade but never found it. Because of the type of woods, it could have easily hidden itself or even have fallen into the river and floated downstream. I remember hearing about a lag screw problem with MT years ago but can't remember the details. I got in touch with MT and relayed the story but not sure where it went. I just hope the issue has been dealt with before it happens the someone else.

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Re: Basic empty weight

Postby GAHorn » Fri Jun 02, 2023 5:27 pm

Joe, are you certain it was an MT prop with the lag screw problem… not an Aeromatic..?

I ran into a similar problem with NTSB on another accident in which a 172 crashed in a canyon. NTSB blamed the problem partially on the fuel selector valve (same type as the 170B) which had the O-ring and the ball-valve reversed…claiming it shut the fuel Off and therefore resulted in engine-stoppage.

I contacted the lead investigator and pointed out that, while NTSB is correct that the IPC shows the incorrect order-of-assembly of the valve parts….. the incorrect assembly will result in Failure of the valve to Shut Off fuel flow….NOT to result in failure to allow fuel flow as NTSB claimed.

The lead investigator had no interest in correcting the error in her report. :(

(This matter was addressed by me in a Fuel Valve Rebuild article published in the 1st Qtr 2011 “The 170 News” found/downloadable here: https://cessna170.org/download/24/170-n ... r-2011.pdf
'53 B-model N146YS SN:25713
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An originality nut (mostly) for the right reasons. ;)
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Re: Basic empty weight

Postby Joe Moilanen » Fri Jun 02, 2023 8:41 pm

GAHorn wrote:Joe, are you certain it was an MT prop with the lag screw problem… not an Aeromatic..?

I ran into a similar problem with NTSB on another accident in which a 172 crashed in a canyon. NTSB blamed the problem partially on the fuel selector valve (same type as the 170B) which had the O-ring and the ball-valve reversed…claiming it shut the fuel Off and therefore resulted in engine-stoppage.

I contacted the lead investigator and pointed out that, while NTSB is correct that the IPC shows the incorrect order-of-assembly of the valve parts….. the incorrect assembly will result in Failure of the valve to Shut Off fuel flow….NOT to result in failure to allow fuel flow as NTSB claimed.

The lead investigator had no interest in correcting the error in her report. :(

(This matter was addressed by me in a Fuel Valve Rebuild article published in the 1st Qtr 2011 “The 170 News” found/downloadable here: https://cessna170.org/download/24/170-n ... r-2011.pdf

It was an MT for sure George. Sounds like the NTSB isn't as thorough as they should be in either case...sad deal...
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Re: Basic empty weight

Postby redacted » Fri Jun 02, 2023 11:33 pm

Wyoming1 wrote:
redacted wrote:Mine on 8.50's is 1420. On 29's it's 1444.

Lyc O-360 Avcon conversion, MT prop. 175 wings, sportsman cuff, AK bushwheels tailwheel. Def some pounds added on, I think the sportsman kit is 20#


This is interesting to me. I have the same engine conversion (170A model), Hartzell prop, standard wings and wheels and am at 1270#. I took the back seat out and dropped another 31# putting me at 1239#. Which MT prop did you put on? That is definitely on my wish list as are the 8.50's.

Thanks for the input.


Prop is the 2 blade 83" constant speed. I could take the back seats out but there are already Atlee Dodge jumpseats and just fold up so I never bother to remove them.
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1952 170B
N2282D S/N 20434
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Re: Basic empty weight

Postby GAHorn » Sat Jun 03, 2023 11:38 am

rnealon1 wrote:I had my '54 170B with stock C-145 engine and no major modifications weighed a few years ago:

BEW: 1330 pounds
CG: 39.70"

This was within 14 pounds and 1" of the calculated BEW and CG, based on the original Licensed Empty Weight.

Bob


It’s been stated (elsewhere, and by persons unknown) that Cessna did not actually weigh each airframe….but instead had determined the typical weight/c.g…. and posted that… calculating any addt’l equipt, as ordered.

My E.W. per actual weighing after restoration is 1345 lbs., and C.G. (per memory) 41.
'53 B-model N146YS SN:25713
50th Anniversary of Flight Model. Winner-Best Original 170B, 100th Anniversary of Flight Convention.
An originality nut (mostly) for the right reasons. ;)
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Re: Basic empty weight

Postby ghostflyer » Sun Jun 04, 2023 1:32 pm

That was an interesting story on the Mt props. About 10 years ago a brand new Super Decathlon [180hp] was in landing mode [touch down] when the pilot [who I know very well and believe his list of events ] said it felt a giant hand had picked up the aircraft and was swinging it around . He lost control and it ended up in a 4ft drain beside the runway.
my company did the retrieval of the aircraft and stored in my hangar. One of the prop blades had hit the mud and had splintered it but there was a clean break of the missing prop blade .The missing prop blade couldn’t be found and it was stated it would be in the mud of the drain somewhere. Both the insurance company and the NTSB stated the pilot had ground looped the aircraft . The pilot of the Super Decathlon was adamant there was no ground loop.
About 18 months later ,I am setting up my crab pots in the mangroves which borders the runway and some thing bright yellow caught my eye . It was the yellow prop tip of the missing blade . It was stuck in a fork of a mangrove tree. There wasn’t any leading edge damage what so ever as it had not hit any mud surface. Plus it was about 90 yards away from where the aircraft had turned right and travelled into the ditch. This was on the left side of the aircraft . no body wanted to listen . So I gave the half blade to Ben the pilot as a Momento.
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Re: Basic empty weight

Postby Joe Moilanen » Sun Jun 04, 2023 2:41 pm

ghostflyer wrote:That was an interesting story on the Mt props. About 10 years ago a brand new Super Decathlon [180hp] was in landing mode [touch down] when the pilot [who I know very well and believe his list of events ] said it felt a giant hand had picked up the aircraft and was swinging it around . He lost control and it ended up in a 4ft drain beside the runway.
my company did the retrieval of the aircraft and stored in my hangar. One of the prop blades had hit the mud and had splintered it but there was a clean break of the missing prop blade .The missing prop blade couldn’t be found and it was stated it would be in the mud of the drain somewhere. Both the insurance company and the NTSB stated the pilot had ground looped the aircraft . The pilot of the Super Decathlon was adamant there was no ground loop.
About 18 months later ,I am setting up my crab pots in the mangroves which borders the runway and some thing bright yellow caught my eye . It was the yellow prop tip of the missing blade . It was stuck in a fork of a mangrove tree. There wasn’t any leading edge damage what so ever as it had not hit any mud surface. Plus it was about 90 yards away from where the aircraft had turned right and travelled into the ditch. This was on the left side of the aircraft . no body wanted to listen . So I gave the half blade to Ben the pilot as a Momento.

That is very interesting...kind of obvious what happened in my opinion. I hope they've got the problem figured out or do so soon before someone gets hurt.

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