C of G for O-360 conversions
Moderators: GAHorn, Karl Towle, Bruce Fenstermacher
- daedaluscan
- Posts: 497
- Joined: Fri Apr 20, 2012 7:03 pm
C of G for O-360 conversions
I have just bought an STC to put an 0-360 on my B model.
I am considering props and have been offered an 80” Hartzell with the harmonic balancer. Anyone running that setup who can tell me weight and C of g?
I would actually like to know any 0-360 conversion C of G, fixed pitch or constant speed.
Any input or advice appreciated.
I am considering props and have been offered an 80” Hartzell with the harmonic balancer. Anyone running that setup who can tell me weight and C of g?
I would actually like to know any 0-360 conversion C of G, fixed pitch or constant speed.
Any input or advice appreciated.
Charlie
1956 170B C-GDRG #27019
1956 170B C-GDRG #27019
Re: C of G for O-360 conversions
Hey Charlie, mine when it was first done...Delair, Hartzell
Weight (lbs) Arm (inches) Moment (lb2s*in)
1426.0 ---------- 37.12---------- 52933.12
i don't have the numbers before conversion at hand.
what STC did you get?
Weight (lbs) Arm (inches) Moment (lb2s*in)
1426.0 ---------- 37.12---------- 52933.12
i don't have the numbers before conversion at hand.
what STC did you get?
- daedaluscan
- Posts: 497
- Joined: Fri Apr 20, 2012 7:03 pm
Re: C of G for O-360 conversions
1954 170B on normal tires
1393.5, 38.6, 53833
Avcon, MT MTV-15-B/210-58 CS prop. W&B calculated since weighing in 1993.
1393.5, 38.6, 53833
Avcon, MT MTV-15-B/210-58 CS prop. W&B calculated since weighing in 1993.
- ghostflyer
- Posts: 1395
- Joined: Mon Apr 21, 2008 3:06 am
Re: C of G for O-360 conversions
My conversion is a Delair with a weight of Arm of. Moment of
1432 lbs. 37.9ins. 54246
Plus a sensenich fixed pitch prop of 60ins pitch and dia of 76 ins .
My bird will be a lot heavier due to a heap of STC,s fitted. There is a heap of weight on the nose and was tempered to add weight to the rear of the fuselage . Not a smart idea if one does the maths as it will add to the moment arm when approaching a ground loop.
1432 lbs. 37.9ins. 54246
Plus a sensenich fixed pitch prop of 60ins pitch and dia of 76 ins .
My bird will be a lot heavier due to a heap of STC,s fitted. There is a heap of weight on the nose and was tempered to add weight to the rear of the fuselage . Not a smart idea if one does the maths as it will add to the moment arm when approaching a ground loop.
Re: C of G for O-360 conversions
This is with a 0-320 c/s Hartzell compact, lightweight starter, battery in the back.
1415 lbs, CG 37.94, 53685
I think we had the discussion somewhere in the past, Lycoming engine is lighter but not by much. Small things add up to make the conversion = to the old install. New fibreglass nose bowl adds weight out front. Alternator is lighter than a gen but sits more forward. Same with the exhaust. If you go C/S add the weight of the governor but really there's not much difference until the prop choice, which I think has the greatest impact on where the C of G lands.
1415 lbs, CG 37.94, 53685
I think we had the discussion somewhere in the past, Lycoming engine is lighter but not by much. Small things add up to make the conversion = to the old install. New fibreglass nose bowl adds weight out front. Alternator is lighter than a gen but sits more forward. Same with the exhaust. If you go C/S add the weight of the governor but really there's not much difference until the prop choice, which I think has the greatest impact on where the C of G lands.
Jim McIntosh..
1953 C170B S/N 25656
02 K1200RS
1953 C170B S/N 25656
02 K1200RS
- Kevin Pearce
- Posts: 49
- Joined: Mon Feb 26, 2018 8:03 am
Re: C of G for O-360 conversions
1953 C170B 800 x 6.00 tyres
Avcon 0-360 with 76” Hartzell CS Prop
Empty Wt 1355 lbs
Moment 50258.75
Arm 37.09”
No fuel or oil
Ballast is required in baggage area for some loading cases.
Avcon 0-360 with 76” Hartzell CS Prop
Empty Wt 1355 lbs
Moment 50258.75
Arm 37.09”
No fuel or oil
Ballast is required in baggage area for some loading cases.
- daedaluscan
- Posts: 497
- Joined: Fri Apr 20, 2012 7:03 pm
Re: C of G for O-360 conversions
Thanks so much for all the replies, pretty consistent around 37". This has really helped with my decision making process.
Better with fixed pitch, best with MT.
Better with fixed pitch, best with MT.
Charlie
1956 170B C-GDRG #27019
1956 170B C-GDRG #27019
Re: C of G for O-360 conversions
are you determining CS/non CS or make of prop?
- daedaluscan
- Posts: 497
- Joined: Fri Apr 20, 2012 7:03 pm
Re: C of G for O-360 conversions
CS or not. Id really like to go CS, but I dont want one with the 100hr AD. I have found an 80” Hartzell that does not have it, but it is heavy with the harmonic balancer and Hartzell will only switch th STC to the same type- for $500usd. It is off a 175 and so I cant get the STC swapped.
Charlie
1956 170B C-GDRG #27019
1956 170B C-GDRG #27019
Re: C of G for O-360 conversions
You should be able to find a serviceable Hartzell HC-C2YK-1BF/7666-2 74” with a B-suffix non-AD hub. Might take a bit of time, but the improved hub has been out for more than ten years, so the props are out there.
Last edited by DaveF on Wed Dec 11, 2019 4:18 am, edited 1 time in total.
Re: C of G for O-360 conversions
Go C/S, cool temps off your runway, you’ll see 1600ft/ min. Just those days alone will relieve the sting (AU’s) of a C/S prop. Then on really hot days you’ll easily get off when others may have to wait.
Jim McIntosh..
1953 C170B S/N 25656
02 K1200RS
1953 C170B S/N 25656
02 K1200RS
Re: C of G for O-360 conversions
Anyone running the new composite trailblazers? Those should be pretty light
- daedaluscan
- Posts: 497
- Joined: Fri Apr 20, 2012 7:03 pm
Re: C of G for O-360 conversions
I think this is the way I am going to go. None of this makes any financial sense so I may as well do the thing right.DaveF wrote:You should be able to find a serviceable Hartzell HC-C2YK-1BF/7666-2 74” with a B-suffix non-AD hub. Might take a bit of time, but the improved hub has been out for more than ten years, so the props are out there.
Charlie
1956 170B C-GDRG #27019
1956 170B C-GDRG #27019
Re: C of G for O-360 conversions
I have a 54 170B with a wide deck O-360A1A Avcon conversion and 80 inch Harzell with the balancer. I would call the performance outstanding and this installation because of the balancer has no rpm range restrictions.
1487.2 pounds at 38.27 weighed about 10 years ago by someone other than me. Has 8.00 tires, double puck Clevelands, factory camera hole aft of pilot seat, baggage door, Javelin fuel tank (24 pounds at 99 inches) com and transponder and an much heavier interior than it needs to be. Flies fine. I plan to lighten up the interior and reweigh the plane myself in the spring.
Dave Stoots ant Stoots Aviation in Fairbanks, AK will sell you an STC to install the 80 in prop on a 180 hp 170 and doesn't care what airplane it came off. A friend on mine ran into the same problem with Harzell when he tried to install a 80 inch off a Husky and was told it was not in the "correct" serial number group to be installed on a 170 and he would need to buy a new prop. He called Stoots and they issued him the STC for $500, it made the installation affordable by being able to buy a used prop.
Tim
1487.2 pounds at 38.27 weighed about 10 years ago by someone other than me. Has 8.00 tires, double puck Clevelands, factory camera hole aft of pilot seat, baggage door, Javelin fuel tank (24 pounds at 99 inches) com and transponder and an much heavier interior than it needs to be. Flies fine. I plan to lighten up the interior and reweigh the plane myself in the spring.
Dave Stoots ant Stoots Aviation in Fairbanks, AK will sell you an STC to install the 80 in prop on a 180 hp 170 and doesn't care what airplane it came off. A friend on mine ran into the same problem with Harzell when he tried to install a 80 inch off a Husky and was told it was not in the "correct" serial number group to be installed on a 170 and he would need to buy a new prop. He called Stoots and they issued him the STC for $500, it made the installation affordable by being able to buy a used prop.
Tim