Thorp Air Command - T18.net

Congrats Jeff. I agree with Lee. These little scooters get under your skin. I come home from four days of flying commercially and can't wait to get the Tigress airborne.
Enjoy! If you need anything, sing out.
Cubes

Thanks!

Actually what is this troubleshooting resource you have that Jeff J mentioned? Could you email me the documentation or link? Jeffbinder@gmail.com

I don't have a clue. Wind was gusting 20+mph from the front right quarter and I was feeding the throttle slowly to ensure no surprises. I am glad the wind was from the right. In case you don't know... on a clockwise spinning prop it helps counter torque and gyroscopic effect so the airplane doesn't pull left as hard. I don't look at the ASI when landing either. The last time I looked at it yesterday was to ensure I was below 100 mph when I lowered the flaps. I did land long and had to terminate a bounce by pulling the stick into my gut. The bounce was because I made the mistake of looking at and feeling for the runway instead of letting touch it down when it was done flying. Before I fly it again I think I will make a couple of high speed taxi runs with the tail up to help me get use to the "picture".

Troubleshooting thing Cubes suggested that I liked was to get the engine up to power and when it stumbles try to lean it out. If it smooths out then you "know" the mixture is too rich. I would recommend tying it down to do it but it could be done anytime.

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Thorp T18
O-320-B3B (160 HP)
68x74 Sterba Propeller

"The joke in aviation is, 'If you want to make a million, you'd better start with £10m.' " -Bruce Dickinson

Roger that!

I don't watch gauges much on landing either. I make sure I'm 85 or higher across the numbers but once I start flare I'm outside of the cockpit until I get more hours under my belt.

Next time you take off can you get a little reference on the airport and see what an approximation of take off roll is? I just look at intersections at my airport and can get an estimation. I'm just trying to compare numbers a little to see if I'm in the sweet spot of everyone else.

It is taking me about 900 feet to get off the ground on a grass strip with a 2-4 mph tailwind and no flaps. I weigh about 190 and had around 22 gallons in the tank. That was my 3rd takeoff in it so I may improve. I also started a little too close to the edge and got in the combine tracks which gave a me good shaking. NORMALLY that is the smoothest part of the strip. 2400 rpm was indicating 145 mph. At one point in a climb (100 mph 1800 fpm) my EGT got to 1300°. I don't think I saw more than 350° CHT. Oil temp was 170°. My idle mixture needs adjusted so I was leaned a touch (pulled out about a 1/2") during the entire flight because I didn't push it in for takeoff but I never truly leaned it either. I typically won't below 3,000 feet MSL and that was as high as I went and that was only for about 5 minutes. Density altitude on the ground was ~1,900. If there is any other info you would like, I will try to remember next the next time I get to play.

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Thorp T18
O-320-B3B (160 HP)
68x74 Sterba Propeller

"The joke in aviation is, 'If you want to make a million, you'd better start with £10m.' " -Bruce Dickinson

Wow, great detail! Thanks for all the info. 900 feet sounds nice. I think my power is a little lacking to get that and my skills still need improvement. I think that should improve when I fix my most likely rich condition.

I went over to the paved runway this evening. 5 mph wind from the left front had me off the ground in less than 800 feet 3 times (one was closer to 700ft). The takeoff on the grass was about the same length with a left crosswind. I wish my landings were that smooth. I started getting a little crooked on the second landing and my right foot got hung up so I couldn't make corrections. When I got it back to the shop I swapped a couple of bolts end for end to get the threaded ends away from my shoes. I may swap those bolts for flight control clevis bolts so I can have a rounded surface against my shoe. I am not sure what I want to do about the rest of it. My toe hangs up on the fuel tank mount strap if I have to raise my right foot to use the brake (ie soft pedal). I may need to change the geometry a little to accommodate my boots. Normally I wouldn't raise my foot but I was heading for trouble and the brake decided it needed to be pumped once to get pressure just then. I didn't have an issue on the first or third landings. I don't think I have used the brakes on the grass.

Is it normal on Thorps for the tailwheel steering to feel like it is hard mounted to the rudder pedals? Every other TW aircraft I have flown, that isn't free castering with a lock, has some give between the pedal and the steering.

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Thorp T18
O-320-B3B (160 HP)
68x74 Sterba Propeller

"The joke in aviation is, 'If you want to make a million, you'd better start with £10m.' " -Bruce Dickinson

Keep the cables tight on the Thorp.

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Bob Highley
N711SH
SN 835
KLAL

Ditto what Bob said . Second thing I would do is spend about 1 hour and bleed the brakes (assuming you have no leaks in the system , master cylinder , caliper, etc.) . You should not have to "pump" the brakes to get a good pedal . A "firm" pedal is what you want . In fact with your heels on the deck your toes should be pretty close to the top of the pedal . Not sure if a smaller shoe would be a better fit than the boots ? It was a good idea to reverse the bolts .

RB
Boom Chicky Boom

I don't have much if any give (play) from pedal to steering. Basically touch the rudder and it's moving. It was a tough transition for me because the citabria wasn't near as sensitive to inputs. Depending when you ask me I love how tight it is or despise it. Hah

That's a pretty good takeoff distance on the 290.

It shouldn't take an hour to bleed one brake....although it may take that long for me to wiggle into position to connect the overflow catch jar. If I ever build an aircraft myself I do believe there will be an access panel for bleeding brakes! If I hadn't of screwed up the landing it would not have been an issue. Since I did, it revealed a couple of inconveniences I need(ed) to take care of.

I hated my commercial pilot training. I did it in a Mooney 20C and had to wear tennis shoes because there was no room at the rudder pedals. I just wear a size 9. I understand a home built aircraft being built around the builder but the Mooney surprised me. Everyone at Mooney must have had small feet when that thing was built.

The picture shows what I am hanging up on. I already changed the 2 bolts on the pedal and that may have fixed the problem because that should allow me to slide my foot back down if I ever need to raise it up again. I also think I need to reverse the bolt on the fuel tank mount strap (visible though the notch) just to be safe. That is what my toe caught on.

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Thorp T18
O-320-B3B (160 HP)
68x74 Sterba Propeller

"The joke in aviation is, 'If you want to make a million, you'd better start with £10m.' " -Bruce Dickinson

Sorry if I mislead you. I have an O-320.

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Thorp T18
O-320-B3B (160 HP)
68x74 Sterba Propeller

"The joke in aviation is, 'If you want to make a million, you'd better start with £10m.' " -Bruce Dickinson

Ah, that explains it!

Now I don't feel so bad for being down in power.

I had forgotten you stated you had an O-290 in the first post. Do you consider it to have 125 HP?

Have you had a chance to try leaning it out to fix the "stumble"?

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Thorp T18
O-320-B3B (160 HP)
68x74 Sterba Propeller

"The joke in aviation is, 'If you want to make a million, you'd better start with £10m.' " -Bruce Dickinson

I dont bleed brakes, pump the fluid in from the caliper up into the cilinder using a thumb pump oil can, no bleeding required the air evacuates as the system fills with fluid, just takes a few minutes......Dan