What can you expect from the ThrustLine modification? We are asked this question all the time. Listed below are some of the advantages and disadvantages of this modification. These points listed are not claims by ThrustLine Products of Alaska, but rather results from pilots in the field from two years of installs and thousands of flight hours. On the following pages are some of the pilot reports in the pilots own words.
Increased Cruise Speed:
Average reported cruise increase of 4 to 10 percent depending on how the cub is equipped etc… At $3/gal gas, a working 180hp cub burning 10gal/hr, with a 10 percent increase in cruise, could possibly see a savings of $6000 over the 2000hr TBO interval.
Example- (representative of most cubs)-If it took 2150 rpm to fly straight/level/clean, after the ThrustLine install, it will take approximately 150 rpm less to do the same maneuver—2000 rpm. Very efficient at this “loiter speed”. Excellent cost savings for survey or recreational flying.
Slower Approach Speeds/Landing Speeds:
Reported Stall speed decrease of 4 to 10 percent. Landing and approach speed is why this mod was initially developed. If you read the pilot reports, you will find pilots reporting slower landing speeds/approach speeds and the solid feel in this area of flight.
Improved Takeoff Performance:
We have seen up to 30 percent decrease in Takeoff roll. With the ThrustLine installed, what pilots have found, on a short field Takeoff as soon as there is an inch under the tires, the airplane is climbing and accelerating. There is no settling back to gain airspeed to climb out.
On floats with the ThrustLine mod installed there is a significant performance increase as the ThrustLine pulls you through the hump phase and onto the step with a load. This translates to shorter Takeoff in time and distance. The increased prop clearance gets the prop out of the erosion zone. With other gear, you can get prop clearance with extended gear or tundra tires. This mod is the only one for increased prop clearance on floats.
Decreased visibility over the nose/ Cowling lines may change/ More power to raise tail:
These items are concerns to pilots installing the mod. While these are real issues, if you pay careful attention to the pilot reports, you will see that these concerns are not much of an issue to most pilots once the mod is installed and the benefits are realized.
Please Take Time to Read the Pilot Reports
have tried to let the ThrustLine mod sell itself. We have purposely
relied on pilot reports and word of mouth in the last two years instead
of advertising and aggressively marketing this product. If you are
interested in this mod—please take the time to read these pilot reports
as you will see the field results from pilots like yourself. There
is quite a bit more info on the SuperCub.org
Below are pilot reports as posted on http://www.supercub.org/. The ThrustLine modification has an average install time of approx three hours. This allows the pilot to go out and do some before tests, install the mod and do some after tests the same day. I have asked the pilots to post results of the performance changes on Supercub.org as it is THE forum for information regarding Supercubs on the web. ThrustLine Products does not want to lock anyone in to buying our product and not receive the expected results. These kits are mailed out to the customer. We tell the customer that if they like the kit they can purchase it---if not---send the kit back. These kits are not a small investment at 1800 dollars a kit. This is just a lead in to the pilot reports to illustrate that the pilot reports are prior to the pilots purchasing this kit---and---the results must have been satisfactory to justify the cost of the kit. Please excuse the spelling etc… below. These pilot reports were copied directly from the SC.org website as they were posted.
Pilot Report—B Prevost---160hp cub
I Picked my plane up last week with a fresh new Lycon 160 engine and the thrustline Installed. The thrustline Is one of the best mods a guy could do to his cub. I've been flying this cub for a long time, even with the 160 engine installed made a huge difference but I could tell the difference with the thrustline right away! Take off was outstanding!, there was no sinking in the short field take off , pulled it off short, It was positive rate of climb,right NOW! no sinking at all. Short field landing, performs very well. And, if you you do start to sink it only takes a little bump on the throttle to stop the sink compared compared to a 150- 200 RPM. There are three other's that have flown this plane and they will also tell how great this airplane flies. My hat goes off to Wayne Mackey for the rebuild of this plane he did a great job. Also Jeff Skyberg and Dave Hartman. Jeff rebuilt this excellent engine, and Dave talked me into the thrustline. Allen Kasemodel your next!
Pilot Report—Jeff---reporting on the above cub
I installed Brian's new engine i took it out and flew it for a couple of hours then installed
the Thrustline and flew it again. The before flight was nothing special,
not the worst and not the best just normal Cub, nothing special. The
after flight was impressive! The take off roll was dramatically shorter
with instant climb after liftoff and lighter more responsive controls.
A wonderful airplane to fly. As far as the engine is concerned
I just put it together the crew at Lycon are
the ones that worked their magic on it.
Pilot Report—Mike Collins---160hp cub
recently installed Marks thrustline mod on my cub. Before install we
measured the angle of incidence and determined the bird to be thrustline
worthy. Its a 160 cub with a few goodies on
it, nothing to special. Leading edge cuff, VG's, 31" bush wheels,
ect. It weighs around
1150 lbs. Before install I took it up with a note pad and ran a few
tests and penciled down some numbers. After install I did the same.
Results after install are as follows. 50 rpm increase in full power
level flight. Five to seven mph gain in full power level flight. Five to seven mph gain in normal cruise. Two mph decrease in
power off stall, full flaps. Required 100 rpm less
to maintain 70 mph level flight. The airplane feels more solid
in slow flight. It comes off the ground sooner and just "grabs"
better if ya know what I mean. I like it.
Pilot Report—Loni -–Cub pilot in the “Big Rocks and Long Props” video.
For Mark @ Thrustline,
and all you other cubdrivers out there who
have ever considered this mod!
If you ever wanted to see who uses the big tires try www.www.cubdriver749er.com
Pilot Report—Phil Mattison---180hp CubCrafters Cub
Pilot Report—Dave Hartman---160hp cub
Wayne Mackey and I started on my cub this morning
at 8:00 am. We installed the TL mod and was pushing the cub out the door when I looked at my watch
at 10:15 am. It went on very nice and easy with no problems with fit
Pilot Report---M Hack---180hp CC cub on Amphibs
Finally got around to having
the Thrustline mod installed on my CubCrafters
amphib last week.
Flew up to Big Lake and Mark measured my plane. Harder to measure because
of my belly pod but the numbers did not seem favorable to Mark. I decided
to take a chance and see if it would work. Mark has a great money back
Pilot Report---Steve T---160hp CC cub
OK ALL You CUB PEOPLE......About this mod.....I decided to try it on for size. My Cubcrafters PA18 160 ported and flowed by Lycon, 31 inch bushwheels, all the good stuff.....The skeptic in me says it all sounds to good to be true....I've got a lot of time in taildraggers and a fair amount in cubs.....so I wont bore you with all of the details....just a few words to sum it all up.....Holy cow.....You have to try it. My cub is faster and it is slower 14 MPH on the top and I haven't actually figured out how slow on the bottom...... before........ I'd drag it in behind the power curve, airspeed indicator pointing uselessly toward the heavens, just hanging there on the prop.....Then chop the power it drops on the whatever like an anvil and you have returned again unscathed. So when i try this familiar oft repeated maneuver post mod what happens when the throttle comes back to the stop............The airplane continues to fly unaided by gasoline for another 200 feet.....So in the ensuing touch and goes I am too chicken to fly slower but too short of time to go out and actually see what airspeed will result in a power on and power off stall....I will do that soon....but for now I can definitely say it is a bunch slower than it used to be.
Pilot Report---JM Fejes---160hp cub
Concerning the trust line mod.
Pilot Report—Billy Vollendorf---180hp cub
I have owned the same Cub for 18yrs and have averaged
700+ hours a year in it. It used to be a stock wing 160hp Cub which
I had flown over 12
Pilot Report---Mike Olsen—180hp exp cub(Mike Olsen Dodge—supporter of the Valdez Flyin)
Eric,everybody I know that have the thrust line mod Myself included find better
ect.Plus if you don't like it use the money
back warranty.Mike O.
Well Folks, I recently installed the Thrustline mod, and first of all I would like to say that Mark is really a pro; dedicated to his product and the customers satisfaction. He would not accept a dime until he knew I was completly satisfied with the mod. Where else can you find those ethics? Lets start with my cub, a 1957 160hp on floats with 5000 hrs. It was rebuilt several years ago with the usual mods and micro VG's. As for the thrustline, Mark supplied the measurments, and all was within his parameters. The installation was quite routine. The new spacers went on easily, with no need to modify any wiring, oil or fuel lines. The cowling rails went even smoother, and I believe my cowling fits better than before. Now, I'm just a float pilot, so I cannot speak for it's performance on wheels. Take off feels more powerful. It pulls up onto the step more quickly (especially with a load) and is at redline rpm from the beginning. Cruise speed is about 8 mph faster, and the really interesting thing is the wing has far less angle of attack (tail flying higher). It seems that to achieve the same cruise speed as before, it now requires about 150 rpm less. When climbing at the same airspeed as before (say 60) the climb angle is now much higher. The aircraft now feels much more solid at lower airpeeds (especially on approach) with a more noticable throttle authority. You just tweak the throttle to adjust decent rate. I'm still getting used to it, but I am a believer that its the best mod on the plane, and it makes it a safer plane.
Pilot Report—Jim Wheat---160hp cub on straight floats
I just returned from my first long trip with the mod. Two people, gas in the belly tank, and gear. We did a number of takeoffs from a 4600' lake. My cub is 160 hp on straight floats. I have done this trip a number of times without the mod so I was anxious to comare the performance. Boy, am I a satisfied customer. In cruise at 2450 it's 9 mph faster. The wing flies much flatter with a load than before. In takeoffs at the lake, it was on the step much faster than before. In landing config, its much more responsive to the throttle.
Pilot Report---Clint---180hp cub
I recently installed Marks (with Marks help) zero
thrust Mod on my 180hp PennYan conversion
cub. I first learned of this Mod about a year ago and finally decided
to take the plunge!! I was not so sure after the first flight in gusty
winds if I was going to keep the mod but after flying in better conditions
the only down side I can find is loss of visibility while taxiing!!!
The largest single improvement is in the landings.... feels more like
a stock light cub, takeoffs are better and cruise is 4-5 mph faster.
Pilot Report—Lanny Merritt—comments on Clint’s cub above
just thought I'd add a comment on Mark's new mod.I
have a fair amount of time in supercubs,mostly off airport so I'm not a novice.I flew my partners 180 hp.cub
before the zero mod and after.It is really
a dramatic improvement.There is a gain in
speed of four or five mph,but the impressive thing is how much slower the approach
speed is.And not dragging it in nose high
with power.It is a very comfortable attitude,and corrections are made with small power adjustments.One more thing,I have
known Mark for more than a few years,you wont
get a bs story from him,you will get good
Just wanted to comment on Marks
Pilot Report—Gunny---180hp cub/Slotted wing
Well we put Mark's mod in my SC last night and
have only put about two hours on it since. The first noticable change is 110mph indicated on the airspeed indicator
verus 100mph before in straight and level
flight with light winds and 2500 rpm.
Pilot Report—Mike Butterfield---(Builder) of Gunny’s 180hp cub/Slotted wing cub
Hello Mark! Thanks for your efforts getting this mod approved and installed on Gunnys plane. It has made a noticable difference in his indicated air speed and the A/C does seem to be lighter in pitch with more authority in the three point attitude. Sure enjoyed the demonstration that Billy put on with his Penn Yan Aero Cub, and I hope to be able to fly like he does when I grow up. Can see where they will benefit even more from this mod than the stock mount. Thanks for being such a wonderful host Mark, and good luck with your endeavor, if we at Air Classic can help, please allow us. Fly low. avoid the radar. Mike Butterfield
Pilot Report—Mark Drath—160hp non elec cub Also a frequent contributor to Cub Clues Newsletter
Put the thrust line mod in today, did some testing,
and thought I'd give some initial results.
Pilot Report—Bob Breeden—160hp cub (edited for length)
AkPA-1 asked me to be candid about the Thrustline
Pilot Report—Bob Breeden—160hp cub –Later report
Pilot Report—Will F.—180hp widebody cub
Pilot Report—Terry—160hp cub
While I can't site numbers, given that
my cub was in the hanger (annual, ski changeover and Thrust Line kit)
for over 5 weeks and too many environmental changes happened between
the "before and after", I can say, unequivocally, that I am
very happy with the mod.
Pilot Report—Larry Goodman—180hp cub and a man of many words!
I got my thrustline on. It's faster , It's slower , It has my kind of people behind it . Larry
Our sincere Thanks to all who have taken the time to post pilot reports on the http://www.supercub.org/ website.