C-85/C-90/O-200/F-19 Performance

[akndrifter]

I have been doing a lot of thinking and pondering. I'm not planning on getting rid of Miss T, but may be having a need for another winged flying machine (and may want to upgrade Miss T eventually). I earned my tailwheel endorsement in one of the Ruess' tcarts, but other than that I don't have any experience in a tcart with more than 65hp. I guess what I'm wanting to know is how do the "higher" powered tcarts perform in different configurations (light, and at/near gross) in regards to take-off, landing, cruise, fuel burn, etc. Thanks for the help.

[AndyDuke]

Re: C-85/C-90/O-200/F-19 Performance

I uprated my Taylorcraft from 65hp to 85hp about 5 years ago (the engine was an A-75 but was limited to 2300rpm so I doubt it was performing above 65hp). Average fuel burn on the 85 is about 10% higher than the 65. Max indicated straight and level speed is up from about 100mph to 110mph but the biggest difference is in climb performanace. At gross weight the climb changed from about 450fpm to 750fpm, this of course is influenced by prop, mine being a mid range 71" x 43" McCauley 1B90/CM.

Andy.

[akndrifter]

Re: C-85/C-90/O-200/F-19 Performance

Thanks for the help. Did you gain any empty weight after the change? Also was there a noticeable difference in ground roll?

[AndyDuke]

Re: C-85/C-90/O-200/F-19 Performance

No gain in the empty weight due to the engine change, the 65 and 85 weigh the same give or take a couple of pounds. I tend to use gross weigh figures because that gives the best comparrison at known weights. The ground roll was greatly improved, I think that will be linked to climb performance but will be prop dependant. Ground roll is now .. advance throttle, count to three, pull back, climb away.

It cost a lot at the time but was well worth it.

[jdlowrey]

Re: C-85/C-90/O-200/F-19 Performance

Ward:

If you get over to Bethel or conversely I get to Dillingham, you're more then welcome to take a ride in my 100 hp so you can form your own opinion.

I switched planes from a 65 hp to a 100 hp. The noticeable difference to me is in climb and somewhat faster cruise as well as increased fuel burn.

Jeff

[Robert Lees]

Re: C-85/C-90/O-200/F-19 Performance

I swapped out my A-65 for a C-85 on the short mount (but with the Don's Dream Machine mods) earlier this year. On the dynamometer, at 100 rpm below the max rpm, the rebuild shop got 93hp, so the engine probably delivers close to 100hp at full rpm.

The shorter take-off roll and vastly increased rate of climb are the main benefits. With the wing structural mods previously done, our gross weight went up from 1200 to 1280lbs, so with two lard-arses and full 24 gal and max baggage, we are slightly closer to gross weight than we were before.

At 2500rpm we can make 115-120mph, but obviously at the detriment of economy. We tend to cruise at the same 100mph indicated airspeed that we did with the 65, and the engine turns at about 2100 to achieve that (the 65 would turn at 2250-2300 for the same speed).

In essence, our average fuel consumption has increased by about 3 or 4 pints an hour...a small price to pay for the increased performance.

[Chet Peek]

Re: C-85/C-90/O-200/F-19 Performance

I've owned and flown the A-Models, BL and BC65's and an F-19. Now fly a DC-65;, but that is another breed of cat. The biggest difference I noticed between the F-19 and the BC-65's was the heavy feeling and an increase of about 15 MPH cruise. (115) All will float half-way down the strip if you are a little fast. The A Models didn't like too much load, but the rest would carry almost anything. Of course I only weigh 125, wlhich makes any airplane fly better.
Rob, I just made reservations for Brodhead. Had to stay at Janesville, full at Monroe.
Chet.

[akndrifter]

Re: C-85/C-90/O-200/F-19 Performance

It seems like most of the F-19s are 900lbs and up. I'm wanting to keep everything to not much more than 800 lbs(with bushwheels), is that a realistic goal? Mine was around 730 or 740ish lbs. I already have 24gals of fuel, and she preforms very well already. How much weight is gained by going to the -12 models?

[Robert Lees]

Re: C-85/C-90/O-200/F-19 Performance

Mine was around 730 or 740ish lbs.

My first thoughts are: The scales are lying.

Second thoughts:
Which model?
What year?
When was the W&B last done with calibrated scales?

Rob

[VictorBravo]

Re: C-85/C-90/O-200/F-19 Performance

It seems like most of the F-19s are 900lbs and up. I'm wanting to keep everything to not much more than 800 lbs(with bushwheels), is that a realistic goal? Mine was around 730 or 740ish lbs. I already have 24gals of fuel, and she preforms very well already. How much weight is gained by going to the -12 models?

It will take a dedicated effort to get a high power T-craft to 800 pounds, but it is probably do-able. Leave the starter and generator off, you'll save a bunch right there and they're not really needed. Look into the Stewart Systems covering process, it is reportedly a lot lighter (and easier) than others. Leave out the leather interior and most of the soundproofing. Leave out the headliner and door upholstery because you get more room as well as saving a couple of pounds. The one worthwhile weight-increasing mod is the skylight, you want that definitely. A wood prop will save weight but decrease overall performance. To get to 730 or 740 pounds on a post-war airframe, you might have to leave the passenger door off, and that is a useful thing, but not necessary. Most of the ultra-low weights happened one brief moment at the factory because they didn't put in the co-pilot control yoke, brakes, or a seat cushion. Beware of chasing a ghost that you'll never catch.

If you really want to save weight, make a new set of doors and get them field-approved. A few pieces of aluminum tubing, a tubing notcher, and a welding shop will yield at least 10 or 15 pounds of weight savings compared to the horrifyingly heavy T-craft doors... even if you cover them completely with 1/16" Lexan for "patroller" doors. The fun part is that you can bow the doors out a little like the modern EXP kitplanes do, and gain another inch or three in width. The best part is they bolt on and off so you are not modifying an airframe permanently.

The -12 engines I think are not too bad if you leave off the starter and generator. If you're really adventurous those magnetos weigh 4 to 6 pounds each or better, and the newfangled electronic LSE ignition systems give you better performance, economy, reliability, easier starting, lower fuel burn, etc. etc. AND they weigh a lot less. That is something you would have to install between annual inspections, by the way, and only on one side for fail-safe reliability! But I honestly have personally flown in the LSE Vari-Eze test aircraft and eye-witnessed it flying at less than 3.5 gallons an hour on a steroid-ed O-200 delivering high cruise power at nearly 200 mph.

[Dano"T"]

Re: C-85/C-90/O-200/F-19 Performance

My 90HP T-Craft is 800lbs on wheels. Then we weighed it on floats and it was 921lbs....I have taken off with 5gals and myself on wheels in 70 ft....I can get up on floats in 6 to 8 seconds....My other T-Craft has a C85-8 and weighs 824 on wheels...even with a 71-42 McCauley the 85 doesn't even compare to the 90 with the 76AK-40...I cruise at 108 wheels and 93 floats. It's a hoot. My 65HP T-craft is fun too (pre-war)...I describe the difference like this....the upgrade to 85 from 65 is like the upgrade to 90 from 85.....Only flew a 100HP once and it wasn't quite the performer my 90 is .....but pretty good.

[T-Rex]

Re: C-85/C-90/O-200/F-19 Performance

T-Rex has the full Harer conversion with a C85-12, KY96 com, KT76 transponder with encoder, full airtex interior, Clayton skylight, landing and nav lights powered by an alternator and brought to life with the heavy old original continental starter and 8.50's. It performs great with just myself (195) and the nose tank full, 400-500ft take off roll and on a standard day I get 750 to 900fpm, mac 1B90 71-44 prop. At or near gross wt. 1500lbs, I'll eat up 750 to 1000ft. of runway depending on how hot it is and how long the grass is, right now it's almost knee high. We have tall trees on one end of our 1900'x50' runway but you can fly out in a turning departure or approach if you are brave. The weight and balance has been calculated for a while but the mechanic who did the conversion stated that they weighed the plane and and now with the bigger tires and a light weight battery I weigh about 870lbs. However I would like to weigh the plane because I am suspicious. If I could build one I would take a post war fuse, because of the stronger tubing and build a C-85/O200, port and polish the cylinders, and throw a Sen.M76AK-2-40 on for a prop. I would probably keep the starter, Sky-Tec light weight for connivence and just recharge a light weight battery to power it. Any body want to trade T-Rex for all the parts I just listed? My wife would kill me.

Brad

[akndrifter]

Re: C-85/C-90/O-200/F-19 Performance

My first thoughts are: The scales are lying.

Second thoughts:
Which model?
What year?
When was the W&B last done with calibrated scales?

Rob

I don't think the scales are lying. It was completely stock. It was 738 (I think) before the bushwheels. How hard was it to get the C-90 approved? I think I can keep her light by doing a similar baggage to Dano"T"s. Is it possible to make the doors entirely clear on a '46 BC12-D? This would be something I would be working on over several years. I am thinking of a -12 series and leaving off the starts [etc], until I can no longer hand prop it myself. Thanks for the collective wisdom!

[akndrifter]

Re: C-85/C-90/O-200/F-19 Performance

I have taken off with 5gals and myself on wheels in 70 ft

How much wind?

[1938BF50]

Re: C-85/C-90/O-200/F-19 Performance

Jeff Lowrey,

See if you can't get Amos up in your Taylorcraft soon. He is looking at buying a plane for training and I can't for the life of me get him to consider the Taylorcraft. He is back at Grant for the next week and a half. THanx