Results 1 to 38 of 38

Thread: Cruise prop and climb prop pitch for C90-12

  1. #1

    Join Date
    Aug 2020
    Posts
    34
    Post Thanks / Like

    Cruise prop and climb prop pitch for C90-12

    New owner of a PA-18-95 that has a C90-12 and came with two props. One is a Mac 71-46 cruise prop and the other is a Sen 76-2-42 climb prop. Can others with more experience then I confirm those are correct/desired pitches for each? My home strip is at 1200í Elevation in North Central Iowa. Most of our flights will be local hops around our lake and almost always out of our 2700í strip. At the same time we will likely be flying along with a 150hp Super Cub and a GCBC. So Iím leaning towards sticking with the cruise prop but am most curious to know if a 46 pitch is indeed a desired cruise pitch.

    Thanks,
    Andy

  2. #2
    Utah-Jay's Avatar
    Join Date
    Aug 2020
    Location
    Heber City, UT
    Posts
    273
    Post Thanks / Like
    We here at SuperCub.org like airplane porn, so let’s see it

  3. #3

    Join Date
    Aug 2020
    Posts
    34
    Post Thanks / Like
    All because of a WTB ad I made on here a few weeks ago... 1960 PA-18-95

    Click image for larger version. 

Name:	8835BF7F-675D-4BE8-9ABA-9A7A241B3942.jpg 
Views:	344 
Size:	91.8 KB 
ID:	53339
    Thanks supercrow, MZ18 thanked for this post

  4. #4
    Utah-Jay's Avatar
    Join Date
    Aug 2020
    Location
    Heber City, UT
    Posts
    273
    Post Thanks / Like
    Beautiful bird

  5. #5

    Join Date
    May 2012
    Location
    SE Montana
    Posts
    375
    Post Thanks / Like
    Glad you found a good one!
    Anybody know when Piper quit building the 95hp Super Cubs?

  6. #6
    RaisedByWolves's Avatar
    Join Date
    Feb 2005
    Posts
    4,467
    Post Thanks / Like
    I maintain a 57 and 58 factory 90hpís. Both of those have double groove trim, higher gross weight and flap pulley mounts.


    Sent from my iPhone using Tapatalk

  7. #7
    Crash, Jr.'s Avatar
    Join Date
    May 2015
    Location
    Anchorage, AK
    Posts
    608
    Post Thanks / Like
    The Sensenich 76AK-2-XX (42 seems good for a 90hp) is the benchmark for climb performance on small cont's so that's a good one to have. Spendy too so if you picked it up with your cub that's a good buy.

    The Mac 7146 is definitely more towards the cruise side but is just a good all-around performer. Picks up speed over the Sensenich but doesn't give up a ton of short field/climb performance to it either. Both really good props to have on hand and both very expensive to buy new.

    If you're dead set on the Mac it's a good prop but the Sensenich is widely regarded as a better performer for most things but gives up a few MPH in cruise. On that slick little 18-95 you shouldn't have any problems keeping up with a big engine cub but the Scout would probably outrun you. Or you can get used to going slow and just meeting your friends a few minutes "fashionably" late.

  8. #8

    Join Date
    Sep 2003
    Posts
    7,496
    Post Thanks / Like
    You lucky guy!

  9. #9

    Join Date
    Dec 2010
    Posts
    53
    Post Thanks / Like
    Very nice, AND a clean drip tray - ENVY!

  10. #10

    Join Date
    May 2008
    Location
    Upper Peninsula of Michigan
    Posts
    669
    Post Thanks / Like
    That's Purdy! I have a Sensenich 76AK-2-40 on my C90-12F Taylorcraft on floats.....It's a wonderful prop. the 42 pitch you have will be a great combo with the C90. As was mentioned here....that is the primo prop for a C90 PA18. Nice job.

  11. #11

    Join Date
    May 2012
    Location
    SE Montana
    Posts
    375
    Post Thanks / Like
    Quote Originally Posted by RaisedByWolves View Post
    I maintain a 57 and 58 factory 90hp’s. Both of those have double groove trim, higher gross weight and flap pulley mounts.


    Sent from my iPhone using Tapatalk
    I thought all of the 95's had the flap pulleys and double groove pulleys...? Didn't they all have a 1500# GW?

  12. #12

    Join Date
    Aug 2017
    Posts
    42
    Post Thanks / Like
    Wow! Beautiful! Does it have electricity?


    Sent from my iPhone using SuperCub.Org

  13. #13
    BC12D-4-85's Avatar
    Join Date
    Feb 2016
    Location
    Fairbanks, AK.
    Posts
    2,879
    Post Thanks / Like
    Try some static rpm runs, climb performance, and cruise with both and let us know the results. Lots of info on either prop but rarely on the same engine. Nice Cub!

    Gary

  14. #14

    Join Date
    Aug 2020
    Posts
    34
    Post Thanks / Like
    Quote Originally Posted by J3Jim View Post
    Wow! Beautiful! Does it have electricity?


    Sent from my iPhone using SuperCub.Org
    Yes, this one left the factory in 1960 with the C90-12F and still has the original pull type starter installed. It may be on the chopping block in the near future as I will likely be installing a light weight starter.

  15. #15

    Join Date
    Jan 2003
    Location
    nd
    Posts
    3,723
    Post Thanks / Like
    put the 76-42 on and when you go traveling the 71-46, but i doubt you will ever take the 42 off. i have a 40 and once in awhile i wish i had a 41 or 42 pitch.

  16. #16
    Crash, Jr.'s Avatar
    Join Date
    May 2015
    Location
    Anchorage, AK
    Posts
    608
    Post Thanks / Like
    Quote Originally Posted by Andy Meyer View Post
    Yes, this one left the factory in 1960 with the C90-12F and still has the original pull type starter installed. It may be on the chopping block in the near future as I will likely be installing a light weight starter.
    I'd give it a go without any starter at all and just hand propping. Small continentals are so easy to hand prop I wouldn't bother with a starter unless you have some physical limitation that precludes it.
    Likes 1934A liked this post

  17. #17
    Doug Budd's Avatar
    Join Date
    Feb 2015
    Location
    Crawford Nebraska
    Posts
    236
    Post Thanks / Like
    Sensenich ground adjustable???
    Then you can change pitch without changing prop.


    Sent from my iPhone using SuperCub.Org
    Likes Farmboy liked this post

  18. #18
    Crash, Jr.'s Avatar
    Join Date
    May 2015
    Location
    Anchorage, AK
    Posts
    608
    Post Thanks / Like
    Sensenich ground adjustables for the O-200 are all experimental as far as I've heard. Plus the shorter of the two (72" I think?) had problems with causing crankcase cracks due to weird harmonic vibrations. Talked to Sensenich about them a month back or so.

  19. #19
    cubdriver2's Avatar
    Join Date
    Apr 2003
    Location
    upstate NY
    Posts
    10,728
    Post Thanks / Like
    Quote Originally Posted by Crash, Jr. View Post
    Sensenich ground adjustables for the O-200 are all experimental as far as I've heard. Plus the shorter of the two (72" I think?) had problems with causing crankcase cracks due to weird harmonic vibrations. Talked to Sensenich about them a month back or so.
    Love mine, never could find a "good" reason not to use it. Bendix blamed some mag problems using it. But I know 2 different Legend Cubs with over 1000 hrs on it. My Ex 0200 SC on 31s would go 111mph pitched at 52 WOT level and still have decent climb

    Glenn
    "Optimism is going after Moby Dick in a rowboat and taking the tartar sauce with you!"

  20. #20

    Join Date
    Feb 2016
    Location
    Rochester, NY
    Posts
    156
    Post Thanks / Like
    I have a Sensenich adjustable on my plane. 0-235. Works great. Haven’t tried in on floats yet but it is smooth and pulls hard on take off while cruising 110.

  21. #21
    Crash, Jr.'s Avatar
    Join Date
    May 2015
    Location
    Anchorage, AK
    Posts
    608
    Post Thanks / Like
    Good to know. I had looked at buying one but was warned off by a few people. And yes, that's what it was- killing magnetos, not case cracks; thanks for clearing that up.

  22. #22

    Join Date
    Aug 2017
    Posts
    42
    Post Thanks / Like
    Wow that is the exact a/c Iím interested in. Had a J3 c90 n loved it! hand propping not for me.

    What is GW EW and fuel capacity?

    How do these perform compared to a J3 C90?

    Thank you for feedback and congrats!


    Sent from my iPhone using SuperCub.Org

  23. #23

    Join Date
    Aug 2020
    Posts
    34
    Post Thanks / Like
    Quote Originally Posted by J3Jim View Post
    Wow that is the exact a/c Iím interested in. Had a J3 c90 n loved it! hand propping not for me.

    What is GW EW and fuel capacity?

    How do these perform compared to a J3 C90?

    Thank you for feedback and congrats!


    Sent from my iPhone using SuperCub.Org

    Gross weight on all -95ís is 1500lbs. Empty weight on this one is in the 9ís. Still has original pull starter, generator, and heavy/rear mounted battery so a few pounds could be loss... This one has 18gals in each wing... so 36gal total.

  24. #24

    Join Date
    Aug 2017
    Posts
    42
    Post Thanks / Like
    Thank you. You burn about 5.5 GPH?


    Sent from my iPhone using SuperCub.Org

  25. #25

    Join Date
    Aug 2020
    Posts
    34
    Post Thanks / Like
    Quote Originally Posted by J3Jim View Post
    Thank you. You burn about 5.5 GPH?


    Sent from my iPhone using SuperCub.Org
    I only have 4.5hrs on it and that was non-stop on my flight home with it. Our weather has been crap since getting it home so I havenít had a chance to fuel it and see what I burned but looking at the indicators I had to have burned about 5gals/hr... I know people fly the C90 all across the board on RPM but this one seems to run smoothest at 2350... so almost that entire 4.5hrs was at 2350. Could probably have done a little better if I wanted to.

  26. #26
    cubdriver2's Avatar
    Join Date
    Apr 2003
    Location
    upstate NY
    Posts
    10,728
    Post Thanks / Like
    Quote Originally Posted by Crash, Jr. View Post
    Good to know. I had looked at buying one but was warned off by a few people. And yes, that's what it was- killing magnetos, not case cracks; thanks for clearing that up.
    "Allegedly" only Bendix mags

    Glenn
    Last edited by cubdriver2; 12-31-2020 at 05:47 PM.
    "Optimism is going after Moby Dick in a rowboat and taking the tartar sauce with you!"

  27. #27
    Farmboy's Avatar
    Join Date
    Jan 2016
    Location
    Glens Falls, NY
    Posts
    2,706
    Post Thanks / Like
    Quote Originally Posted by cubdriver2 View Post
    "Allegedly" only Bendix mags

    Glenn
    Also only the older prop that is no longer made.
    The new Sensenich 76Ē ground adjustable was the hot ticket on the C90 that I had. Transformed that airplane.

    Pb


    Transmitted from my FlightPhone on fingers...

  28. #28
    cubdriver2's Avatar
    Join Date
    Apr 2003
    Location
    upstate NY
    Posts
    10,728
    Post Thanks / Like
    Quote Originally Posted by Farmboy View Post
    Also only the older prop that is no longer made.
    The new Sensenich 76Ē ground adjustable was the hot ticket on the C90 that I had. Transformed that airplane.

    Pb


    Transmitted from my FlightPhone on fingers...
    Mines old style, works just fine

    Glenn
    "Optimism is going after Moby Dick in a rowboat and taking the tartar sauce with you!"

  29. #29
    skywagon8a's Avatar
    Join Date
    Mar 2008
    Location
    SE Mass
    Posts
    11,235
    Post Thanks / Like
    Quote Originally Posted by cubdriver2 View Post
    "Allegedly" only Bendix mags

    Glenn
    Quote Originally Posted by Farmboy View Post
    Also only the older prop that is no longer made.
    The new Sensenich 76” ground adjustable was the hot ticket on the C90 that I had. Transformed that airplane.

    Pb
    Quote Originally Posted by cubdriver2 View Post
    Mines old style, works just fine

    Glenn
    Glenn what type mags do you have? This is the first mention I've heard of this issue. Was it just a one time event? Was it something else (like someone mucking something up) and then blaming the mags and prop? Or was it really a resonance issue between the prop and mags? How many times have we seen a mandatory inspection/alteration of some type when the original issue was someone covering up a mistake or some type of abuse which was not normal.
    N1PA

  30. #30
    cubdriver2's Avatar
    Join Date
    Apr 2003
    Location
    upstate NY
    Posts
    10,728
    Post Thanks / Like
    Pete, first time I saw that prop on a plane was on Mike Harts Legend Cub up on the Ramp at Greenville Me. That was also the first time I met Mike. Maybe 15 years ago or longer. I always spent time hanging around the Sensenich booth at Kosh and was familiar with the prop from talking to them. Back then I was friendly with Ed Zerker from Sensenich and we had talked about that prop becoming legal. I asked why they didn't make it 74 or 76" and he said that 72 was the limit without having harmonic problems. I lusted for one for quite a few years. Talked to the guys at Sensenich every year and the opinion was that they pulled the prop because there were 2 planes that had mag problems, both with Bendix mags running that prop. Bendix blamed it on the prop and Sensenich got scared of the liability.
    I have Slicks, and I talked to Mike who was still running that prop before I bought mine used on here.

    Glenn
    "Optimism is going after Moby Dick in a rowboat and taking the tartar sauce with you!"
    Thanks skywagon8a thanked for this post

  31. #31

    Join Date
    Sep 2002
    Location
    Southern NH
    Posts
    912
    Post Thanks / Like
    SENSENICH PROPELLERS
    2008 WOOD COURT
    PLANT CITY, FL 33563
    PHONE –(813)752-3711
    FAX – (813)752-2818
    14 CITATION LANE
    LITITZ, PA 17543
    PHONE –(717)569-0435
    FAX – (717)560-3725

    NOTIFICATION NO. CN-1-13
    Sept 27, 2013

    TO: ALL AIRCRAFT OWNERS AND OPERATORS USING CONTINENTAL O-200 ENGINES AND SENSENICH C72AE PROPELLERS

    SUBJECT: MAGNETO FAILURES / PROPELLER HARMONICS

    PROPELLER MODEL(S): SENSENICH 2EK/C72AE, 2EL/C72AE GROUND ADJUSTABLE COMPOSITE PROPELLERS

    AIRCRAFT MODEL(S) AFFECTED: ALL AIRCRAFT USING CONTINETAL O-200 ENGINES AND SENSENICH C72AE PROPELLERS

    DISCUSSION:
    Sensenich has been made aware of random magneto failures on Continental Motors Inc (CMI) O-200 series engines that CMI has attributed to operation with the Sensenich composite C72AE propeller. These failures appear to be intermittent and CMI reports that the magneto failures are a result of a 6th
    order vibration that CMI attributes to a vibrational resonance of the engine/propeller combination. While the Sensenich composite propeller is not experiencing any problems related to the resonance referred to by CMI we do acknowledge that the propeller and engine are not mutually exclusive and must ultimately be considered as a system. It is unclear at this time if these issues affect all composite propellers used on CMI four cylinder engines or if it is specific to one particular manufacturer’s propeller model.

    Sensenich has traditionally approved propellers for use on aircraft engines based on a vibration survey of the propeller and endurance testing per 14 CFR part 35 or ASTM F2506. Vibration surveys record what is happening in the propeller as a result of operation on a particular engine and this data is then used to determine the airworthiness of the propeller on that particular engine configuration. All propeller/engine combinations exhibit vibrational harmonic interaction. It is not possible to design a propeller that will not exhibit vibrational harmonics within the operating envelope when run on an internal combustion engine. The Sensenich C72AE propeller has been vibration tested in accordance with ASTM F2506 and has been determined airworthy for use on the CMI O-200 series engines. Sensenich has not historically determined the airworthiness of the entire propeller, engine, airframe combination but has provided data, typically to the airframe manufacturers, in support of those efforts.

    As a result of these magneto failures CMI is requesting that Sensenich discontinue recommending and selling composite propellers for use on CMI four cylinder engines. Although the vibration survey has demonstrated the C72AE propeller to be airworthy when operated on the CMI O-200 series engines and there are numerous installations that have successfully logged in excess of 300 hours without magneto failure, it cannot be shown with certainty that the C72AE propeller is not causing the issues with the CMI magnetos. For these reasons and in the interest of aviation safety, Sensenich has decided to temporarily suspend sales of the C72 series propeller. If at a later date the CMI O-200 series engines can be proven compatible with the C72AE propeller then sales of the C72AE propeller will continue.

    ADDITIONAL INFORMATION:
    Sensenich is currently in the testing phase of an additional composite propeller, the C76, designed for use on the CMI O-200 engine. The C76 propeller has exhibited significantly different vibratory characteristics from the C72AE propeller and the vibration survey of this propeller on a CMI O-200 engine is scheduled to be completed by early October of this year. Pending successful completion of the vibration survey and related endurance testing per ASTM 2506, Sensenich will release the propeller for service.

    Although Sensenich designs propellers for aircraft engines and airframes based on horsepower, rpm, and aircraft speed, the suitability for any particular propeller for an application is the responsibility of the aircraft manufacturer or aircraft owner.

    If you have any questions related to the information disclosed in this letter or to discuss any propeller options available for your application during this time please contact Sensenich directly.




  32. #32
    skywagon8a's Avatar
    Join Date
    Mar 2008
    Location
    SE Mass
    Posts
    11,235
    Post Thanks / Like
    It would be interesting to learn the nature of the particular magneto failures. What exactly failed? A wire break? Or something more serious? Sometimes just repositioning some little thing makes a difference.
    N1PA

  33. #33

    Join Date
    Feb 2016
    Location
    Rochester, NY
    Posts
    156
    Post Thanks / Like
    Mine is the new style adjustable. I had the old style and for some strange reason it caused high cylinder head temps. Sensenich took it back. Now the new style is great. I have a76AK42 that I use on floats that maybe for sale this summer if the adjustable works good on the water. I do have about 6 different keys for the old style if some one (Glenn) wants them. Free for the asking. Oh yes, my plane has an 0-235 LYC and Slick mags.

    Jim

  34. #34
    cubdriver2's Avatar
    Join Date
    Apr 2003
    Location
    upstate NY
    Posts
    10,728
    Post Thanks / Like
    Jim if you have a 50 I'd like to try it. I ran a 52 pitch for the last 2 + years but now have the 48 in for skis. They make keys from 32" to 60" in 2" increments

    Glenn
    "Optimism is going after Moby Dick in a rowboat and taking the tartar sauce with you!"

  35. #35

    Join Date
    Feb 2016
    Location
    Rochester, NY
    Posts
    156
    Post Thanks / Like
    I will look over the weekend and will pm you if I have. You can have them all and go crazy

  36. #36

    Join Date
    Sep 2002
    Location
    Southern NH
    Posts
    912
    Post Thanks / Like
    Spoke with Sensenich yesterday to get it straight from them. They assure me a certified ground adjustable for the small Continentals is in the works and hopefully it will happen next year. Won’t hold my breath on the timing, but will keep my fingers crossed....

  37. #37
    Farmboy's Avatar
    Join Date
    Jan 2016
    Location
    Glens Falls, NY
    Posts
    2,706
    Post Thanks / Like
    Quote Originally Posted by mam90 View Post
    Spoke with Sensenich yesterday to get it straight from them. They assure me a certified ground adjustable for the small Continentals is in the works and hopefully it will happen next year. Wonít hold my breath on the timing, but will keep my fingers crossed....
    Bear in mind they have a 118 experimental blades to build, 130 pre orders for O-320ís they canít build until certified, and 140(?) for O-360ís. To say aviation exploded last year is an understatement.

    Plan ahead.


    Transmitted from my FlightPhone on fingersÖ

  38. #38

    Join Date
    Sep 2002
    Location
    Southern NH
    Posts
    912
    Post Thanks / Like
    Quote Originally Posted by Farmboy View Post
    Bear in mind they have a 118 experimental blades to build, 130 pre orders for O-320’s they can’t build until certified, and 140(?) for O-360’s. To say aviation exploded last year is an understatement.

    Plan ahead.

    Transmitted from my FlightPhone on fingers…
    Yep...... I suggested they work through their lunch hour.....
    Likes Farmboy, RaisedByWolves liked this post

Similar Threads

  1. Climb or cruise prop?
    By womblesd in forum Cafe Supercub
    Replies: 17
    Last Post: 08-17-2019, 05:31 PM
  2. Cruise Prop vs. Climb Prop
    By j3jm in forum Cafe Supercub
    Replies: 7
    Last Post: 04-24-2019, 01:50 PM
  3. Cruise vs Climb Prop Takeoff Performance
    By scrappyf16 in forum Products, Purchases, Reviews & Prices
    Replies: 10
    Last Post: 06-08-2018, 09:55 AM

Bookmarks

Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •