Curtiss Jenny Restoration

Welcome! We hope you enjoy following the restoration process of a 1918 Curtiss JN4D Jenny. Once completed, the aeroplane will be flown and displayed at the Candler Field Museum in Williamson GA (30 miles south of Atlanta). You can contact me below by clicking on "VIEW MY PROFILE"

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Location: Peachtree City, Georgia, United States

Thursday, April 25, 2013

Exhaust system

It's been a busy couple of days! Brian and I drilled and installed the turtledeck hinges.


And the grease fittings were cut sown and installed on the wheels.

Now the fun part - we started tack welding the exhaust together. It was proving to be a frustrating build.  We would align the new pipe on the engine, mark the flange, tack weld.  Check it.  Mark the next flange, tack it.  Realize that the darn thing moved a little.  Cut off the tack weld.  Try it again.  And so forth.

During all of this, the old exhaust was not far from our mind.  Why were we not using an original piece of the aeroplane?

For one thing, the flanges didn't fit. We already made new flanges, right?  There were a few dents and dings. Hmmm...they were not that bad.  Plus the dings gave the stacks a certain patina.

It was decided to switch gears and try to use the original exhaust.  We could always make a new one if things didn't work out.

Off came the old flanges.

As you can see, the exhaust stack was made from round tubes.  The Hisso exhaust port was oval.  What can we do about that?

 The initial shaping was done in a vice. 

Then a lot of hand work with done with a ball peen hammer.


There we go - one oval exhaust tube.

We learned a few things when we made the new exhaust.  We were constantly battling alignment of the tubes.  Since I prefer oxy-aceteline welding, I could not tack weld right on the engine. The heat would be too great.

So, we dusted off the MIG welder.  After a few practice welds, I felt comfortable enough to tack weld the pipes right on the engine.


The exhaust was removed and I returned to my familiar and trusty oxy-aceteline torch.

Here is a new flange welded onto the original exhaust. After all the flanges are attached, the exhaust will be cleaned up.  In particular, we are going to send it to be thoroughly cleaned inside. I'm considering having it ceramic coated for preservation too, but that decision is not definitive.

Lastly, we gave the propeller a trial fit.  More about that soon.  Wait till you hear this saga....

More soon



Friday, April 19, 2013

Alaska Jenny

Friends Ben Guttery and my old neighbor Kirk Baldin sent me a link to an neat news article today.  It seems as if the folks in Alaska have made great progress on Ben Eilson's old Jenny. 

I heard about this Jenny a few years ago when John Morak contacted me looking for some Jenny drawings. John is an expert wood worker and he was going to build a set of wing struts for this Jenny. 

My hat goes off to all the volunteers brought Ben's Jenny back to life.  Good job!


Fairbanks residents are anticipating the return of their most iconic aviation artifact to Fairbanks International Airport this fall.

 The 1923 Curtiss Jenny flown by aviation legends Ben Eielson and Joe Crosson was removed when the terminal was expanded and it settled into a lengthy refurbishment under the care of the Pioneer Air Museum and Experimental Aircraft Association (EAA), FAI chapter -- Chapter 1129. Coordinated by member Roger Weggel, an airframe and powerplant (A&P) instructor at the University of Alaska Fairbanks, the Jenny has been taken apart and reassembled with great care. But Weggel is quick to point out this isn’t a new plane.
This Jenny will never be museum quality. Rather, the Eielson/Crosson aircraft sports evidence of work done by all the men who took care of the aircraft the past 90 years, including highly regarded Alaska mechanics Jim Hutchinson and Frank Reynolds.

The Jenny was purchased as a surplus vehicle from the U.S. military in 1923 by city leaders. According to Jean Potter’s “The Flying North”, published in 1945, pioneer banker Dick Wood put up most of the money. It arrived in crates on July 1 with its 90-horsepower OX-5 engine and had its first flight only three days later with Wood onboard and Eielson flying. 

“Someone HAD to go,” News-Miner editor W.F. Thompson wrote later, “so Dick decided it might as well be him. It was disturbing however, he continued, “(to see) two of the best men in town, everybody’s friends, settin’ one behind the other in a rig not much wider than a canoe...”  

Thankfully, the flight was successful, and on the wings of the Jenny, commercial aviation came to Alaska.  In the years that followed, the Jenny was involved -- like every other early aircraft -- in numerous incidents and accidents.

Eielson, who may be best known for flying the first airplane across the Arctic Ocean, soon began flying a Liberty-powered De Havilland for the postal service, and by the time of his death in a Hamilton Metalplane in 1929, the Jenny had likely seen several other pilots.

Crosson, the pilot who made the first landing on Mount McKinley in 1932, flew it soon after arriving in 1926 (he related a story to Jean Potter about flipping it on landing when flying a miner 70 miles to a claim on the Upper Chena). At some point in this period, Weggel is certain that Crosson became the aircraft’s owner, and in 1931 was responsible for an engine change to the more powerful Hispano-Suiza, which is on it today. This was a common conversion at the time as the OX-5 was widely acknowledged not to be strong enough.

Hanging from rafters 

Over the next 10 years, the Jenny was flown by unknown pilots, although the technology was rapidly outpacing it. Jean Potter saw the Jenny in the company of Fairbanks mechanic/carpenter Frank Reynolds while researching The Flying North in early 1940s. She later wrote:

He took me once to the shed behind the college powerhouse where Eielson’s old Jenny is stored.
“There it is,” he told me, turning a flashlight into the gloom. “There’s Ben’s first ship. We wish we had room to show it better.”
It hung from the rafters, the narrow, tapering fuselage, with the flimsy wings tied ignominiously along its sides. The engine was gone. The paint was scratched and peeling. Reynolds looked as proud as if he were displaying a Superfortress.
“I’ve helped him take her up many times,” he said. “Two or three fellows would hold hands, you know, and the one on the end would reach out and spin the prop. Sometimes took a whole hour to get him going. ‘Contact,’ Ben’d say, ‘switch off. Contact, switch off.’ We’d have to pour ether in the gas. She was stubborn, that engine.”

The Jenny’s original wings were lost long ago, likely in a fire at Weeks Field when undergoing maintenance during the Crosson phase of its ownership. When the aircraft was cleaned up by some airmen and displayed for Eielson Air Force Base’s 10th anniversary in 1953, a set of wings that were stored with it from a Swallow TP were attached in their place. The Swallow was a biplane manufactured in Wichita by a company that employed such future aviation stars as  Walter Beech (Beechcraft) and Lloyd Stearman (Stearman Aircraft). After the military celebration the Jenny was placed back in storage at the university with the Swallow wings attached. There it remained for decades. (The engine was back with the aircraft at this time so must have been in use elsewhere during Potter’s earlier visit.)

It is clear that as much as Weggel and his crew know about the Jenny, there is a lot they never knew:
• How it came to be at UAF, and why it was stored there for so long?
• Is its ownership by the Museum of the North due less to provenance than an assumed responsibility brought by years of having the aircraft under university control?

$22,000 project 

When the decision to refurbish it was presented to the EAA, however, none of that mattered. “The decision was unanimous to fix it,” says Weggel, and so the group of volunteers got to work raising money ($22,000 to date, with a portion still in the bank) and bringing back to life this vital piece of the city’s past.  The Smithsonian National Air and Space Museum provided original plans for the Curtiss Jenny, but it took nearly a year and a half before they could be located and forwarded to Fairbanks. The package included five 35-millimeter microfiche films that dated to the First World War when the Jennys were designed and built. The Eielson/Crosson Jenny likely was manufactured in California at the end of the war,  although no one can be certain. The propeller (not the original) is marked “War Department” and was made for the OX-5. For Weggel that is good enough. The prop is period correct, along with the engine and fuselage. However,  the wings would have to be made from scratch.

 Every Wednesday for years a rotating group of EAA members and UAF students met and worked on the Jenny. They soon discovered evidence of work done in years past and made a decision to respect such alterations and let them stand whenever possible. “We left old repairs and modifications to areas of the fuselage, the landing gear and elsewhere” Weggel said. “We didn’t want the aircraft to be factory new; we want it to carry the mark of what it was part of and how it was taken care of by so many different people over the years. We want it to look like the plane that it was in Alaska.”

Remarkably, the Jenny has been restored to air-worthy condition, although due to its rarity and value (perhaps more than $400,000), it will never fly. But soon enough, it will be back on display for all to see with bright yellow and light blue paint. When that happens, Weggel and his crew will be able to turn their attention to a new project, a hoped-for restoration shop at the Air Museum in Pioneer Park and a build focusing on those Swallow wings. “They came off a plane Crosson flew,” says Weggel, “and we believe it was also flown by Sam White, the first flying game warden in Alaska.”
It’s another big project but as the group has proven, it’s up to the task. The legacies of Ben Eielson and Joe Crosson are safe with the Fairbanks aviation community.

 It’s entire flying life, this aircraft never left Alaska,” says Weggel. “It has always belonged here, to us.” And so the Jenny remains, in the place that knows her best and with an aviation community delighted to celebrate all she represents.

Colleen Mondor is a former dispatcher for a Fairbanks-based air carrier. Her book, The Map Of My Dead Pilots: The Dangerous Game of Flying in Alaska, details her years working in the Alaska aviation industry. You can contact her at  colleen(at)

Exhaust pipes and Wing Walk

Since it was raining today (and I couldn't get any spraying done on the Bucker gear legs) I figured it would be a good time to work on the Jenny exhaust.

A poster board pattern was made using some basic math.  Here is the situation: a cone needs to be made that is 26 inches long and starts with a 2 in diameter and ends with a 3.5 in diameter.  The front of the pattern was cut to 6.28 in. (Diameter or 2 x 3.14) and the bottom of the pattern was cut to 11 inches (Diameter of 3.5 x 3.14).

Once the pattern was checked on the jig, it was transferred to some .025 sheet steel.  Here is where you want to add about 1/4 in onto the sides for overlap.  You will see why in a minute.

Before putting the steel into the slip roller, take a mallet and round the ends.  The slip roller cannot make a curve on the first or last inch.  

Like this.

Then start rolling.

As you go, adjust the rollers to give you a deeper curve.   Tighten one more than the other to give you a cone shape.


When you have the shape you want, remove the steel and put it in your jig.  This is why you added a little material to the sides.  With some tin snips, cut a straight line.  Mark the steel underneath.  Cut it also.  When you are done, you should have two matching seams.

Many tack welds.

Then weld the entire seam.

Here is the cone attached to the elbow.

A trial fit.

The old exhaust is slightly different.  But I used its dimensions to fabricate the new exhaust.

 This is the exhaust I am trying to replicate.  It is flying on the Old Rhinebeck Aerodrome Jenny.

There is a lot more exhaust work to do yet, but this is a good start.

Last night, Leo Roberson stopped by the shop asking if he could "do anything".   Knowing his talents, I put him to work making the wing walk.


The step gets a little bit of the diamond tread too.

Brian Eberle made two new tail wires.  

OK, I'm going to go out on a limb here -

The Jenny will be on display at the Candler Field Museum's Vintage Day event on June 1st, 2013.

It won't be ready to fly, but it will be awfully close.  We plan on having the wings attached, cowlings on, prop attached...there I said it.  Now we have to make due on our promise.

More soon.  Enjoy.


Wednesday, April 17, 2013

Priming cups, grease fittings etc

A package came today from Restoration Supply.  Included was four new Primer Cups.

The Primer Cups thread into the intake tubes.  All you have to do now is fill them with fuel, open the petcock, close the petcock, and swing the propeller.

Also in the box were a set of reproduction grease fittings for the spoke wheels. The original one is on the left.  Notice the threads. They are shorter.  I have to machine down the threads on the new fittings to match.

Lastly, Restoration Supply is the only company to carry the 1920's diamond treas for the wing walks.  The material is really beautifully made, but prepare yourself - it is also very expensive.

For all you future Jenny builders, you can get this stuff from:

Restoration Supply Co.
15182B Highland Valley Road
Escondito, CA 92025

(800) 306 7008

I also ordered the turtledeck hinges from  They are called Desk Butt Hinges Item number 504400.  Basically, they are 2 inch wide hinges.

These hinges must be modified a bit.  The bottom half has to be rounded to match the original profile.

More soon.  The Bucker gear legs are covered and awaiting pinked tapes.  Jenny progress shoud resume Thursday.



Wednesday, April 10, 2013

Jenny movie in post-production

I just got an email from filmmaker Dorian Walker.  His Jenny documentary is now in post-production and should be done soon.  Below is a link to see a nine minute clip of the movie:

 Dorian also sent pictures of his Jenny.  It should be finished right before the movie!

I apologize for the absence of posts - I spent a week down with the flu, flew a long trip at work and the landing gear / brake conversion on my Bucker Jungmann is taking a lot longer than I anticipated.  But that is the way it goes.

Progress on the Jenny will continue soon.  In the mean time, historian Dave Trojan asked a question I could not definitively answer.  He found some pictures of Jennies with machine guns. I explained the way the interrupter gear worked so the pilot did not shoot off his own propeller.  But what I noticed in this picture is the myriad of lines leading to the gun.  Originally, interrupter gears were mechanical - cams and rods.  Later, I remember reading that they figured out how to do it hydraulically.

Are these lines hydraulic?  Pneumatic? What about that pump on the side of the fuselage?

Secondly, here is a picture of a Jenny with a rear gunner.  Again, I explained how there was a ring that raised and lowered the gun automatically to prevent the gunner from shooting off his own tail.  But this Jenny does not have that ring. And the gun does not have a barrel.

Could it be some sort of a training camera?

I was hoping someone out there could answer these questions.  If you know the answer, email me at and I will forward the answers to Dave.

More soon...I promise