Click to return to Steen Aero Lab Homepage  
 
If at first you don't succeed... then unexploded ordnance disposal probably isn't for you.
 
Go to printable version 
 
  Our Aircraft:
 
    Steen Skybolt
Pitts Model 14
Pitts S1
Knight Twister

 
  Products:  
    ONLINE STORE

Products Home
Bruntons Brace Wires
     About Bruntons
MT Props
Hoffmann Props
     Request Prop Quote
Vendenyev M14 Engines
Laminated Wing Spars
Laminated Leading Edges
Canopies
Motor Mounts
Wing Kits & Wing Jigs
Three-Section Wings
Piloti Shoes
VedaloHD Sunglasses
     Styles
     FAA Report on Sunglasses

 
  Builders:  
    Builder F.A.Q.
Construction
   Photos

Articles
Project Gallery
Submit Photos
Project Logs

 
  Resources:  
  News
Event Reports
Email List
Testimonials
Non-US Distributors
Links
Scale Models
Biplane Lore
About This Site
Website Updates
About Us
Contact / Visit Us

 
   

 
ABSTRACT:     Article about Jack Hamblin's 300-hp Skybolt project N9449, which was built in Alaska from early (1974) plans and includes modifications such as electric flaps, adjustable rudder pedals, spring-strut landing gear, and a 38-gallon main fuel tank.
The Agony and the Ecstasy
Jack Hamblin's Skybolt Project
 
(From Sport Aviation, 06/1979, Page 42)
 
By Jack Hamblin
Photography by Jack Hamblin

 
Jack Hamblin (EAA 86780)
P.O. Box 201
King Salmon, AK 99613

It seems only fitting that after a person subjects himself to four and one half years of grueling work, frustration, misery and sacrifice, that the event should not go to nought. I once heard a phrase taken from a well known movie, "There are six million stories out there; this is one of them." So, this is my story and the story of Skybolt 9449.

Living in the outer reaches of southwest Alaska, leaves little to do in the choice of activities. Since I had no desire to add to the state's alcoholic problem, I took up oil painting and a considerable amount of reading. My daytime job was as an aircraft mechanic and A.I. for Peninsula Airways in King Salmon. The Perry Mason books were soon exhausted and aviation reading material was getting short also. In thumbing through the several old editions of SPORT AVIATION, it occurred to me that I might build myself an airplane. Surely a person that has been in aviation since 1948, was a commercial pilot with SEL, MEL and Instrument ratings should be able to tackle this sort of project -- hands down! After long deliberation in looking over all the various kinds and types of aircraft, the Steen Skybolt bubbled to the top of choices. The Skybolt looks so nice and big too.

The plans to the Skybolt arrived in the spring of 1974, and I immediately ordered the fuselage tubing package. There was a runout 300 horsepower Lycoming engine available here at Peninsula, so I bought it as that was the only thing available at the moment.

While waiting for the first batch of 4130 steel tubing to arrive, I busied myself with tearing down the engine, cleaning and micing all the parts and other incidental things. In June the steel tubing arrived on Wien Airlines and I spent the first $500 of the $14,750 that would eventually go into the Skybolt. Building the jig frames, work tables, setting up the power machines by Sears, proceeded in swift order. By July it was ready to lay the first tubing of the fuselage. In some article or someplace, I had heard that to build the fuselage first was better, because it was harder to do. The wings are fun because they are wood. A person is not liable to abandon the project doing it this way. At any rate, the fuselage went together very well, but I had to do a whole lot of planning before hand. After going as far as I could on the fuselage, the wings were started. In several months the constructed parts began to take on some huge proportions and it was no longer easy to get around in my bedroom. The wings were hung on hooks to the ceiling, my bed was moved to the living room, and the sofa was moved into another building. However, this arrangement didn't last too long as it was necessary at this time to mate the wings with the fuselage and build the motor mount. My three room, company furnished living quarters were no longer big enough to hold the airplane and me. So, out came the wall of the bedroom!

Now you might think it awful brash of a tenant tearing down the walls of his apartment, and manufacturing an airplane in his bedroom to boot, but this is the Last Frontier and a fellow can't let these little things stand in his way. If it was good enough for Sam McGee, its good enough for me! However, I must confess that I was working against time to get the critical measurements of mating the wings to the cabanes done, and getting the main wing mounts welded on. The building was an old Army structure from the days when the Japanese were blowing hell out of the Alaskan tundra in 1942. This building and several like it were going to be torn down soon to make room for the new 80' x 80' steel hangar that Peninsula was going to have erected. Therefore, I was working like crazy to get the basic alignments finished before my house disappeared.

July 1976 rolled around and everything I possessed was loaded into a 40' van. Shortly thereafter a large bull-mooser came charging out of the gloom of the morning, went right through my house and tore it flat to the ground. A sheared off water pipe squirted water in the air amidst the wreckage. A large dump truck picked up the junk, including the kitchen appliances, rugs, furniture, water heater, and fixtures. It was all hauled to the dump. I wasn't sure as to where it was my next home would be. As it worked out, the Skybolt was put in one of the Company hangars in Naknek, 15 miles west of King Salmon. There is an old tool shed there that is affectionately called the "bunkhouse" that I moved into with my cache.

The author attacking the fuselage welding with vigor! Looking forward past the Cessna flap motor, its linkage and to the shoulder harness reel.
The author attacking the fuselage welding with vigor! Looking forward past the Cessna flap motor, its linkage and to the shoulder harness reel.

Being settled in now, I devoted my time to some engineering problems I had made for myself. The several changes that were made included making the fuselage 4" longer, installation of a 38 gallon main fuel tank, adjustable foot pedals, installing electric flaps, putting on Maule spring loaded gear struts and fabricating the side mounted cowl flaps. Trying to keep an eye on the weight distribution was difficult. In the reality all I could do was go by what looked reasonable. That big IO-540-K engine and prop were at least 127 pounds more than the Steen prototype. After some rough calculations, the battery was put in the tail of the fuselage, the vertical fin spar was made bigger and thicker walled as was the elevator front spar tubes. In addition I used a Cessna 180 tail wheel strut, and chromed it. As a matter of fact, there are about $1100 worth of chromed parts from one end to the other. The gear struts and aileron interconnect struts are chromed also. All chromed parts were done by Industrial Plating Corporation in Seattle and processed to minimize embrittlement. They did a beautiful job. The wing plates, aileron tubes and other internal wing metal parts were cadmium plated and neutralized. Industrial Plating also chrome plated the aluminum spinner. Try that on for size!

The wing flaps are driven by a Cessna 206 flap motor mounted to the rear of the pilot. This motor drives an idler swing arm connected to two push rods going to the flap bellcranks. Being rather modest, I thought this a stroke of genius.

The adjustable foot pedals were a little more difficult. They incorporate a pull pin between two flap plates. Pulling on the single control knob in the cockpit releases the two plates allowing the pedals to swing free. Releasing the knob allows the pins to spring into the desired hole. The span of adjustment is about 5". The idea for the foot pedals came from the SNJ-5 that I owned for 4 years when I lived in Santa Maria, California back in 1961. I always admired those foot pedals.

Mating the wings: half in the bedroom and half in the living room.
Mating the wings: half in the bedroom and half in the living room.

Well, in every life a little rain must fall. It started "raining" the end of 1976 and part of '77. I had sent out the lower oil case to have an oil outlet boss welded to the case for the engine. The first time it was welded it broke off when the fitting was tightened in it. The second time it was sent out to be welded the company that had it would not do the work. Seems Lycoming makes these alloy cases out of some unusual metals. The third place the case was sent to agreed to do the job, however, it was over 6 months before I was able to get it back... and had to hire a lawyer to do that. I really don't know what the problem was to this day.

The next lump on the head was the fabrication of the 38 gallon main fuel tank. The fuselage diagonal brace tubes run through an aluminum tube tunnel, which in turn runs through the tank area. The diagonals are removable as is the tank. The tank is removed by way of the front cockpit. The cabanes are welded solidly to the fuselage longerons, but some of the forming braces are removable that hold the top fairing onto the fuselage. It was necessary to have the tank heliarced, returned to me, then the tunnels placed through the tank and returned to the welder for finishing. When it was pressurized to 10 psi and checked for leaks, the thing looked like the cheeks of a squirrel with 10 psi of air in it, but it didn't crack or leak. I don't know if it was worth $437 or not.

December 1976 brought on some real rain. It rained and rained. The hangar floor got flooded... then there was a cold spell and the flooded floor froze. Winter then set in for good and the temperatures went to 20 below. Operations had to be suspended because the heater would not keep up with the cold. My tool shed bedroom was also too cold to heat so I had to move in with the neighbors. The loss of 3 months work time was aggravating but there was nothing I could do about it.

About February 1977, the cold eased up a bit and I went back working on the Skybolt. Driving that 15 mile road to King Salmon every day was trying my driving skills. Snow nearly 2 feet thick, ice as slick as something on a stick, and, oh, how the wind blew!

The fickle finger of fate, it seemed, was not through with me yet. I was nitrating the rudder with dope and an electric heater caught it on fire. The flames licked at the fiber board ceiling of the hangar and caught it on fire. The fire was intense for a brief moment. I considered dying in the fire as a sort of "last act of defiance", but the flames quickly died down and I was able to handle the situation with the use of a small fire extinguisher. My heart was in my mouth and my legs were weak, so I sat down and smoked a cigar...! Oh agony, what have I wrought!

The fuselage was finished about April 1977. Where any screw was used I installed a nutplate. There are no sheet metal screws in the airplane except for a few holding name tags in the cockpit flooring. I made a great effort to eliminate all the little cheap and aggravating methods used in aircraft today that every mechanic is familiar with. The greatest benefit is that there are no gear bungees. I hate them things! With the limited access in the under carriage, I could see no way to put those bungees on. The use of the Maule spring struts was suggested by the FAA Maintenance Inspector out of Anchorage, who kept tabs on my progress from time to time.

The time had come to move the Skybolt and myself back to King Salmon. My good friend and coffee drinking buddy, Bill Pinette, helped me load the tools and machinery in and on my beat up old Ford station wagon. We made a tail post hitch on his pickup and he pulled the Skybolt fuselage over that bumpy 15 mile road to King Salmon from Naknek. I had the wings on the station wagon. It was slow progress, but we made it in about 45 minutes. After depositing the sum total in an unused tin shed nearby, we retired to his home to have a cup.

Cessna 180 tail wheel spring. Adjustable rudder pedal. Note the homebuilt lamp.
Cessna 180 tail wheel spring. Adjustable rudder pedal. Note the homebuilt lamp.

Bill Pinette was at that time restoring a crash damaged Beech 17. He had been working on that Staggerwing for over seven years. He started out to just repair it and fly, however, as things go, everything he saw needed work, overhaul or some other attention. He disassembled every part of that machine, overhauled it, fixed it, replaced it or painted it. I marveled at the workmanship and effort he put into that Stagger-Beech. Bill is no stranger to overwhelming odds on occasion. He is not only a very good mechanic, but a pilot as well. He flew B-17's for the 8th Air Force over Germany during the Big War, so has not weak courage nor faint heart. Bill also has another Staggerwing. By the summer of 1978, we banged heads together and filled out all the Form 337's and I signed off these and the Annual Inspections on both aircraft. Later on in the year, September to be exact, Bill invited me to fly with him in one of the Beeches to his permanent home in Kettle Falls, Washington. We saw an awful lot of Canada for those 3 days it took to cover the distance. Canada is a very beautiful country and the people are the greatest.

During the summer of '77, I was feeling pretty cocky and decided to put in an integral fuel tank in the upper wing, made from fiber glass. I designed it to hold 12 gallons. Looked good empty. The aluminum top sealed well with the cavity with capitol authority. A chrome plated Cessna flush tank inlet finished the installation and looked beautiful... but it leaked like a sieve! Well, shoot, I can fix that -- I'll just put in some slushing compound. The slushing compound softened the resin and inside the tank it looked like a worn out oriental rug. I then built an aluminum tank, sealed and riveted together. This tank worked out well but was only 9 gallons because of all this foolishness.

Ah, spring! After spring had sprung I sprang into action. It was 1978 now and the engine parts were all together. The moving parts were electronically balanced, the fuel system was installed and every ferrous part on it was chrome plated. Nuts, bolts, washers, induction tubes and exhaust pipes. The exhaust pipes stick out the sides like a Texas longhorn. They are 3-1/2" in diameter and not the least bit noisy (damn!). All it needed now was the completion of the inverted oil system. I purchased the quality components made by Christen and rigged up a rather complicated system. Using the basic Christen items, I added two #802 ball oil valves. One is horizontal and one is vertical. A feed tube runs to the forward end of the oil sump inside the engine. The other feed outlets are on top and to the rear of the sump. This provides an oil supply in any position the pilot finds himself in, by design or accident.

Calibration of all the instruments took several days. The engine didn't run too well on the initial runup. It seems that way back in aviation history, a mechanic made the first goof-up. It was called the old rag-in-the carburetor trick. That's right, some nit-wit left a nice white rag in the mouth of the injector servo. Boy, is my face red!

Feeder tube in the oil sump with a special outlet fitting. Note the welded boss and screen at the far right... caused much trouble.
Feeder tube in the oil sump with a special outlet fitting. Note the welded boss and screen at the far right... caused much trouble.

In June '78, all of a sudden the airplane was actually finished. It looks nice, but will it fly? It has to fly! Maybe I made a mistake in the weight and balance data. Oh boy, I better have the figures rechecked by somebody that knows better. King Salmon Airport is a joint civilian/military field and there was at this time a fellow who was an aeronautical engineer as head of the Air Force Maintenance Section. I contacted Captain Penpeck and he agreed to do an investigation of the flight parameters. We reweighed the aircraft, trammeled and measured, cussed and discussed the results. Armed with all the figures and airfoil numbers we could dig up, Captain Penpeck retired to his favorite laughing place and started a run-down on the figures. The fly in the soup was the long lipped modified split flaps on the lower wings. He had to extrapolate equations for the flap co-efficient and the lift co-efficients of the wings. His figures later proved to be correct within 2 miles per hour for flap up and flap down stall speeds. I am eternally grateful to Captain Penpeck for his kindness and efforts. As noted previously, the placement of various items of any weight were done on a "guess and by God basis". In the final analysis the center of gravity "envelope" fell right on the money. Thanks to the good Captain, it appeared that I would not end up at the bottom of a 15' crater after all, after the first flight. My "monster" sprouted little angel wings in my mind.

The author straining to fit a 38 gallon fuel tank into what at this point seems to be a 28 gallon fuselage.
The author straining to fit a 38 gallon fuel tank into what at this point seems to be a 28 gallon fuselage.

Twelve July, 1978. The friendly folks from the FAA showed up at King Salmon during their monthly rounds. Mr. Al Fleener, the Maintenance Inspector out of Anchorage, was well familiar with the aircraft as he had been following my progress for several years. There were several problems that took the rest of the day to iron out but he finished his inspection the following day. In the meantime I had taken a flight check and the pressure was building up as "first flight" time rolled around. It was late morning as we pushed the Skybolt out of the hangar and I was a nervous wreck. Several friends were rather concerned about my nervous state, but I had to find out what I was all about.

Lycoming 10-540-K1A5 engine and exhaust system. A number of modifications were made.
Lycoming 10-540-K1A5 engine and exhaust system. A number of modifications were made.

I stuffed myself into the cockpit, helmet, parachute and all. As I tried to settle down a little, it struck me that there were an awful lot of instruments in the panel, and rightly so. Of the 18 gauges, most of them miniature, they included a full gyro panel, ILS with glide slope, VHF transceiver, VOR, ADF and a transponder. In short, full IFR.

IFR panel - Skybolt style. Flap detail... plus electrical and control cable runs. Rudder cables are run outside the paneled cockpit.
IFR panel - Skybolt style. Flap detail... plus electrical and control cable runs. Rudder cables are run outside the paneled cockpit.

The engine fired off smoothly and I cleaned up the cockpit making plans in my mind on what I was going to do. I had made arrangements with the tower for some taxi tests with possible flight afterward. Everything looked good so I taxied out to the runup area. Still looking good, the tower was informed of my intentions and I started a high speed taxi after clearance. Feeding in the throttle slowly to about 1800 rpm the airplane didn't seem to have any tendency to want to swap ends and tracked well, so I added a little more. I didn't feel it leave the ground. It hopped up about 3 feet so I held it there playing with the power and controls to see if it was going to do any wooly-boogers or anything scary. It was, in fact, very stable. Coming back on the power it settled to the ground tracking straight as an arrow. Fascinating! At the end of the 7500' runway, I turned off into a turn around area and informed the tower I was ready for the slam-dunk, in a manner of speaking. Being cleared, I fed in the power for real. The white line down the center of the runway disappeared under the engine as the airplane literally leaped into the air, as if trying to tell me that all this taxi business was a waste of time, as we could have been flying all this time. The engine was putting out a modest 19 to 20 inches of manifold pressure as we swung around the pattern. The stall felt reasonable so I continued on to the landing.

Lining up with the runway from way out, the ol' Skybolt settled onto the runway like a trooper. No swing or sway. I was getting the feel of the airplane and did a touch and go. This time I let it all hang out and put on full power. The acceleration was breath taking and I pulled back on the stick to maintain 90 mph. It slowed to 90 mph alright, but the climb angle was better than 45 degrees! "We" wheeled out to our private test area southeast of the field and began to get serious about this business. The area is deep tundra and small lakes. There is no place suitable for an emergency landing, but that's all there is in any case for lo the many miles. In any case, I found out what the airplane would do. There is little that it can't do. Even though the airplane weighed in at 1496 pounds empty and 2150 gross, that big 300+ horsepower engine pulled that little airplane around like a dog wrestling a squirrel.

"I wheeled and soared and done a thousand things you have never dreamed of..." During that first hour it all came into focus. I yelled, I laughed, I screamed. "I, Jack of Hamblin, made this machine with my two bare hands!" Racing around huge white clouds I would have not traded places with anyone under the whole canopy of heaven. I must have been insane with ecstasy.

Follow Up: "OH, WOE!"
The following blurb was published in the next issue of Sport Aviation (July 1979, page 9):
Among our other problems, a picture was deleted from the story "The Agony and the Ecstasy" by Jack Hamblin of King Salmon, Alaska. We included everything but (sob!) a shot of the completed airplane. So, along with sincere apologies to Jack, here is his Skybolt high over the tundra of our 50th state.

Jack Hamblin's Skybolt

If you have any additions or corrections to this item, please let us know.

Go to Articles archives

 
  Steen Aero Lab      1451 Clearmont Street NE   Palm Bay, FL 32905 USA     
Phone: (321) 725-4160      Fax: (321) 725-3058      Contact Us