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Excerpts from
AAHS Journal, Vol. 57, No. 2 - Summer 2012
Table of Contents 

Jack Conroy and his Flying Fish

      Many large components of the Apollo moon mission systems were being built on the West Coast, thousands of miles from the ultimate launch site at Cape Canaveral, Florida. In order to transport these parts, it was determined they would need to be shipped via water on a barge passing through the Panama Canal on the way to Florida. This method was expensive and very time consuming, taking nearly a month for the passage. John M. "Jack" Conroy, a former Air Force pilot, (already renowned as the first person to fly round trip from California to New York and back between
sunrise and sunset, using an F-86,) envisioned a gigantic cargo plane to carry the mammoth rocket units for the Apollo Program coast-to-coast in a matter of hours. Although the Boeing 377 Stratocruiser was still active as a tanker and military transport, the plane’s life as a civil airliner had waned and the airliner repository at Mojave, Calif., was filling up with retired 377s.
     Because of the bulk of the Stratocruiser’s fuselage, it was an ideal platform for the development of one of the most bizarre modifications in the annals of aviation.
     Conroy set up a partnership with aircraft broker Lee Mansdorf and conceived a stretched 377 with a 20 ft. 3 in. diameter dome over the upper lobe of the Stratocruiser’s double-bubble fuselage. Conroy invested his own money and placed the construction order with On Mark Engineering, who began the conversion at Van Nuys, Calif., in January 1962, on ex-Pan Am N1024V, originally named "Clipper America."
     The first step was to cut the fuselage aft of the wing and insert a 16 ft. 8 in. plug, which had been removed from the forward fuselage of ex-Transocean 377, N107Q. Flight tests of this modification were successfully concluded and it was determined the plane flew even better with the fuselage
extension. Next, the 20-foot diameter tubular dome was built over the existing fuselage. The diameter of the new upper lobe extended into the arc of the inboard propellers, so the tips were
shortened by six inches.
     One morning there was an article in the Los Angeles Times that showed a photo of the plane under construction. I was intrigued and went to visit the Aero Spacelines office, located . . .


Aero Spacelines Super Guppy launches on its first flight

The Last Allison-Powered P-51 Mustang

     This is a story of the XP-51J lightweight Mustang– the aircraft shown in Figure 1. The story is not long as only two of this P-51 variant were built, and they did not fly for very long, nor did they get into combat. Their short history ended when the Army sent them from North American Aviation to Allison for engine testing – until now. Recently some information, including several pictures of the XP-51Js, was found in the archives of the Rolls-Royce Heritage Trust (RRHT), which contains history of the Allison Division of General Motors. This story summarizes what has been known about the XP-51J, some of which is untrue, and the new information found in old Allison and National Archives records. Unfortunately, no flight test reports have surfaced, but some information can be inferred from the pictures that have been found.
     The North American P-51 was a particularly well-designed aircraft. Even though the early Allison V-1710 powered Mustang was 1,500 pounds heavier than a Spitfire IX, it was 38 mph faster at 20,000 feet when both were using 1,000 hp.1 After 1,081 Allison-powered P-51s (including 620 British Mustang Is) and 500 similar A-36As were built, the engine was switched to a 2-stage, 2-speed supercharged Rolls-Royce Merlin built in the U.S.A. by Packard. The additional supercharging gave the Mustang the high-altitude performance that made it famous.  During the remainder of the war, 13,686 Merlin-powered Mustangs (P-51Bs, -51Cs, -51Ds, -51Hs and -51Ks) were built. By the end of the war, 370 of the 555 lightweight P-51Hs, powered by the later V-1650-9 Merlin, had been built, but none were used in combat.2 The remaining 185 P-51Hs were built after the war was over.

The Lightweight Mustang
     Particularly during wartime, there is always a need for higher performance aircraft. Although the P-51 with the Merlin engine was a great aircraft, it was scrutinized for ways to improve its performance. Both the USAAF and the RAF had found that the Mustang was unnecessarily heavy. After reading a report on the subject, General Arnold, Commander of the USAAF, had North American Aviation begin work on a lightweight Mustang, the XP-51F, whose empty weight was to
be less than 6,000 pounds.
     In January 1943, representatives of North American Aviation submitted to the Air Materiel Command a new design for a fast, highly maneuverable, and high rate-of-climb fighter  . . .


Allison-powered P51J Mustang

Arctic Ops Part II: Early Secret Military Cold War Arctic Operations  

Coping with Arctic Weather
     The officers and enlisted men comprising the Cold Weather Test Detachment (CWTD) at Ladd Field, Alaska, continued throughout WWII ground and flight testing USAAC combat aircraft, thus determining their suitability for combat in Arctic climatic conditions. They created new methods to level the critical sub-zero temperatures and their negative effects upon men and machinery enabling both to accomplish their combat missions and safely return to base.
     Practical flight tests and research introduced battery inspection procedures when aircraft cold-soaked overnight. Maintenance personnel checked for specific electrolyte levels, used ground battery carts towed on a copy-cat dog sled and charged them prior to cranking cold-soaked engines.(1)  The popular press reported that aircraft wet-cell storage batteries were being improved with thicker positive-negative plates, improved plate coatings, plus improved electrolyte quality and levels. Post-WWII they still required attention and recharging especially in sub-zero temperatures that reduced their designed power output.
     As WWII erupted in Europe, Luftwaffe aircraft burned 87-octane avgas without antiknock additives. America’s petroleum industry sold overseas buyers expensive 100-octane avgas with tetraethyl lead, thus greatly reducing the antiknock problem. The British liquid cooled and radial engine performance was increased, and even resulted in reduced aircraft takeoff distances.(2)  Unfortunately, the increased percentage of lead in the higher octane gasoline induced spark plug fouling especially in sub-zero temperatures. Cranking extremely cold, excessively-primed engines wetted or frosted spark plugs thus preventing ignition. New long-reach spark plugs with higher heat-ranges (the plug’s electrode reaches further into the combustion area hence closer to the piston crown), were engineered, manufactured and sent to front-line squadrons, including those in Alaska.
     This was highlighted when temperatures dropped to lows of -60 degrees F during the winter of 1943-1944, thus severely cold-soaking the Ladd Field detachment’s aircraft.(3)  Military pilots also requested a quick method of cranking a totally coldsoaked engine. The application of 10 percent to 30 percent gasoline injected into the engine crankcase and oil tank by means of oil dilution systems reduced the hot oil’s viscosity before engines were shut down, somewhat mixing the two liquids.(4) Engine starts were somewhat easier with thinner oil  . . .


Dougals A-20 Havoc in snowbank in Nome, Alaska

Doing the Wright Thing

       It should come as no surprise to readers that the first airplane factory was founded in Dayton, Ohio, or that it bore the name Wright. What may come as a surprise is that those original buildings still stand, and until three years ago they were still part of a functioning factory.
     The Wright Co. Building 1 was only the fifth structure ever constructed by the Wright brothers for their aircraft. It followed the two wooden buildings the brothers constructed at Kitty Hawk, N.C., in 1900 and 1903, and two hangars constructed in 1904 and 1906 at the Huffman Prairie in Dayton, Ohio. The Kitty Hawk hangars were left to the elements, and vandalism, while the Huffman Prairie became part of Wilbur Wright Field, the last hangar being demolished by the Army Air Corps in 1937. With their demise, the National Park Service now considers the Wright Co. Building 1 to be the world’s oldest surviving structure constructed for powered flight. In 2012 it became the focus of a National Park Service plan to turn the Wright brothers’ first airplane factory into a museum complex dedicated to the history of early aviation in Dayton, Ohio.

The Wright Company
     Wilbur and Orville Wright had been trying to sell their Wright Flyer to the U.S. Army since 1905, but not until February 8, 1908, did the Army Signal Corps finally accept a bid from the Wrights for an observation aircraft, with the specification that it be capable of flying 40 mph for 125 miles while carrying two persons. Despite Orville’s disastrous crash in 1908, the brothers delivered their first "Military Flyer" to the U.S. Army Signal Corps in 1909, receiving $25,000, plus a $5,000 bonus
for completing all requirements ahead of schedule. The Army contract meant the brothers could finally move out of their bicycle shop and build an aircraft factory in Dayton. In late 1909 Wilbur and Orville collected $400,000 from a group of New York investors, and the Wright Co. was incorporated on November 22, 1909.
     Initially, the company occupied a rented corner of the Speedwell Automobile plant on Essex Avenue (now Wisconsin Boulevard), an industrial area in southwest Dayton. Speedwell was one of six automobile manufacturers located in Dayton at the time. The Speedwell factory was only intended as a temporary site while the Wright Co.’s first factory building was being constructed. At the Speedwell site the Wright Co. produced the Model B Flyer, the world’s first mass-produced
airplane, and the Model R, a single-seat racing version of the Model B. Meanwhile, Charlie Taylor, Wright’s chief mechanic, continued to build the Flyer’s engines in the back of the West Third Street bicycle shop. The original location of the Speedwell Automobile plant is now a vacant lot at the southeast corner of Wisconsin Blvd. and Miami Chapel Rd. It is marked with a metal sign indicating its importance.
     In January 1910 the Wrights broke ground for the first building ever constructed for the purpose of manufacturing airplanes. The site was in a cornfield on the south side of West Third St., about 1.5 miles west of the Wright’s bicycle shop. The one-story structure was modest, incorporating
a curved roof that resembled an airplane hangar. Inside, it  . . . 


America’s first aircraft factory, The Wright Airplane Co, circa 1911

Air Cadet to Sweden, 1958

      In the summer of 1958, I made my first trip out of the United States, to Sweden, on the International Air Cadet Exchange (IACE). I was one of five American Civil Air Patrol (CAP) cadets who spent two fascinating weeks touring the country, along with pairs of cadets from Belgium, Canada and the United Kingdom. Hosted by the Swedish Air Force (Flygvapnet), we visited air bases and other locations from Kalmar, in the south, to Abisko, well above the Arctic Circle.  We were introduced to Swedish aviation, culture and society, making friends and developing interests that for me, at least, have been important parts of my life ever since. I will attempt to recreate the point of view and impressions of an 18-yearold on his first major international journey. But, first, a brief explanation of the IACE.


IACE History
     Sweden was the fourth country to participate in the International Air Cadet Exchange. The first UK-Canada exchange, in 1947, sent 46 cadets and two escorts from each country. American CAP cadets went first to England in 1948. Canada’s invitation to Flygvapnet brought Swedish Flygpojkarna cadets to Canada in 1950.


Selection for IACE
     I joined the CAP in 1955, in a small eastern Oregon town. The longest journeys I had made, to that time, were annual visits to grandparents in southern California, 1,500 miles away. Sweden was only a name in books, a place lying somewhere north of Germany. By late 1957, I was eligible for the IACE. I successfully passed the selection board that chose me to be one of two from Oregon for the 1958 exchange.


En Route to Sweden
    The journey to Sweden carried me on a variety of USAF airplanes. A small Air Force C-45 transport flew me to McClellan AFB, in Sacramento, California. From there, the cadets from the western United States and Hawaii moved on to Andrews AFB, Md., outside of Washington, D.C., aboard a YC-121F turboprop Constellation. After briefings at nearby Bolling AFB, D.C., we moved on to Germany via Newfoundland and Scotland, aboard a C-118 (DC-6A).
     At Bolling, I met the other four cadets who were going to Sweden. They were Pete Gay, from Maine, Cliff Covey (New Jersey), Larry O’Quinn (North Carolina) and New Mexico’s  . . .


Air Cadets inspect cockpit of Saab A32 Lansen

United States Army Air Forces
Primary Flight Trainers, 1939- 1945

     WWII aviation enthusiasts and Hollywood tend to remember specific fighters, such as the P-51 Mustang or the P-47 Thunderbolt, and bombers, such as the B-17 Flying Fortress or the B-29 Superfortress. Often forgotten or misunderstood are the much smaller and slower monoplane and biplane piston-engine aircraft that were used to train thousands of United States Army Air Corps and Air Forces pilots. These aircraft, built mostly by such companies as Stearman, Fairchild and Ryan, were used in what some deemed the most important stage of a cadet’s training career: primary. Each possessed certain strengths and weaknesses. Some of these aircraft can still be seen flying out of small airports in the United States, offering rides to those willing to pay $50 or more for a half hour of flight. Their occupants probably have no idea that over 60 years ago these airplanes played a vital role in laying a foundation upon which the United States built a mighty air force.
     On September 29, 1938, the day when European leaders reached an agreement at the Munich Conference that was supposed to avert war in Europe, Maj. Gen. Henry Harley "Hap" Arnold, who had just become Chief of the United States Army Air Corps, outlined for President Franklin Delano
Roosevelt the miniscule size and strength of the USAAC in comparison to Nazi Germany’s Luftwaffe.1 Arnold wanted a bigger air force and proposed a plan to produce 4,500 pilots in two years starting in 1939. Primary flight training would initially be provided at Randolph Field, Tex., as well at nine civilian flight schools owned by eight contractors. By 1944, over 60 civilian schools were responsible for providing primary training to all army flying cadets.
     When Arnold formulated his plan, the civilian contractors had fixed-base operations or flight schools with airfields and facilities, years of commercial and military aviation experience, and the flight instructors and mechanics in place, but they lacked the aircraft necessary to carry out flight training. In January 1939, the original eight contractors possessed a total of 24 planes. Even then, the USAAC could only make 86 planes available with another 81 projected to arrive later in the year.
This was far short of the 400 primary trainers proposed for the 4,500 Pilot Plan. Although the 4,500 Pilot Plan was revised downward to less than 2,500, the USAAC was not only short 230 primary trainers, but by law could not loan government aircraft to civilians.
     The USAAC looked to the U.S. Congress for money to acquire the necessary planes. It met resistance from congressmen who, wanting to save money, pressed the military to use aircraft commonly used by the Civil Pilot Training Program. As one congressman asked, "Can you use any of these smaller airplanes like the Cub or the Luscombe or any of those little two-seaters, to do primary training?" Such aircraft were powered by 65- and 100-hp engines and cost only $1,500. The USAAC knew that it needed aircraft with at least  . . .


Stearman PT-17 over Carlstrom AAFB, Florida

"Number Two;" Helicopter Pioneer Stewart Ross Graham

     "I have always been fascinated by the wonders of flight – the flying machines as well as the daring aviators who flew them. The flying machine I came to know best was the helicopter."


 Stewart Ross Graham,
Naval/Coast Guard helicopter pilot number two.


     The airplane in American aviation history has many famous fathers. Hundreds of names are etched in the fabric of fixed-wing aircraft history. The helicopter, conversely, has few, and these pioneers’ stories, with few exceptions, are vague.


"It was " on October 20, 1943, when I recall the words, "Stew, you’re safe for solo,’ from Frank Erickson, my instructor with only a few hours of solo time himself, as he stepped out of the YR-4 helicopter and waited a safe distance away – behind a tree – near the Sikorsky factory in Bridgeport, Connecticut.
"I pulled into a shaky hover, and then watched Frank give me a thumbs up. I smiled nervously and pushed forward making a few circles around the meadow and landed.
"That made me Coast Guard [and Navy(1)] helicopter pilot number two. At that time I had a total of three and a half flight hours in helicopters. It was an extraordinary way to graduate: no written tests, no diploma, no certificate and no curriculum to follow thereafter. I was set free to penetrate the unknown with an unleashed, unreliable, under-powered, vibrating, revolutionary type of flying machine."(2)


     In another account, truer perhaps – more for private confessions – Graham admitted, to his "astonishment" the machine suddenly became airborne, "unexpectedly going backwards and gaining altitude. Instinctively pushing the control stick forward had little response until full forward thrust on the control was applied to overcome the rearward flight. A quick look at the altimeter showed 400 feet gained during this state of total confusion"Regaining flight control I’m now flying over the area where I became airborne noticing the commander gazing pathetically at me with his hands clasped together on his chest as if saying his prayers. I continued flying for several minutes to steel my jagged nerves and to give time to calm my instructor down. I finally landed safely with the commander running up to the helicopter, his face now inside the open window shouting, "Graham’–he calls me Graham now – "what the hell kind of a takeoff was that?’ He normally spoke loud but his voice this time was several dBs above loud." Igor Sikorsky and his chief engineer quickly analyzed the situation. This became a weight and balance problem when the 250 pound Erickson departed the cockpit for Graham to fly solo for the first time.(3)
     Cmdr. Stewart Graham, USCG (Ret.), would be anyone’s favorite neighbor. He is an excellent listener, shy, and with a face framed around a permanent smile; a smile accented with an elfin twinkle in his eyes. He has the uncanny ability to make people in his company feel comfortable and important. His modest demeanor belies an adventurous life, so it was a surprise and a pleasure for me to sit with Stew and listen to him tell his story.(4)


A Boy at the Airport
     Graham, born in 1917, grew up in Rosedale, Long Island, N.Y., about a mile from the Curtiss-Wright Airport. The eightyear-
old, in 1925, rode his bicycle to the airport, spending most of his spare time with the pilots and their airplanes. Pilots grew familiar with this inquisitive lad and soon permitted him to helpd . . .


HNS-1 landing on moving platform, Mal de Mer


Auxiliary Exhaust Ports in Early Aircraft Engines

     A careful look at early Wright brothers and Glenn Curtiss engines reveals a fascinating design feature. Small holes can be seen at the base of their engine cylinders.  The Wright brothers used circular (and later rectangular) "holes," also referred to as "auxiliary exhaust ports," in their 1904 Engine No. 3 as well as their Vertical-4 engines. Glenn Curtiss also used auxiliary exhaust ports in some of his 2, 4 and 8-cylinder aero engines. A few others, including engines from the Kemp Machine Works, Bates Engineering Co., as well as the famous Anzani engine in the Bleriot IX also used this engine design feature. These auxiliary exhaust ports were through holes at the base of the individual cylinders that exposed the inside of the engine cylinder to the atmosphere when the  piston was near the bottom of its stroke. Since these engines operated under the four-stroke cycle principle, these holes, at first, seem rather odd to the modern observer. Who did this and what was
the purpose of these holes in the engine?
     A schematic of auxiliary exhaust ports is shown in Figure 1. This engine schematic represents the F-head type used by Glenn Curtiss in his early engine designs. Near the base of the engine cylinder can be seen a set of three holes that would exhaust to the atmosphere at the end of the combustion-expansion stroke (left side). These were known during the late 19th century and first decade of the 20th century as "Auxiliary Exhaust Ports." The right side schematic shows the conventional exhaust stroke with exhaust leaving the engine’s cylinder via the exhaust valve.
     What was the origin of this design feature? This article will briefly explore the basis for these ports starting with steam engines, two-stroke engines, stationary gas engines and early motorcycle and automotive engines that likely led to the introduction of this design feature by some early aviation engine manufacturers. Some notable early aviation engines that used this concept will be explored in this article. Then, as the Great War arrived, this aviation engine technology faded away.

Steam Engines
    During the later decades of the 19th century auxiliary exhaust ports were present in both stationary and railway steam engines. In general, these auxiliary exhaust ports were part of the valve box that is connected to the working steam pistoncylinder. At least one design, however, used an auxiliary exhaust port that was directly connected to each end of the working steam cylinder (1). The purpose of these "extra’ exhaust paths was to reduce the steam pressure in the working cylinder down . . .   


A Wright Vertical-4 engine pointing out exhaust ports


An Old Geezer’s Story

     Like a lot of AAHS members, I’ve had a lifelong interest in airplanes and aviation history, and even have some stories that might be of interest to others. What follows is one of them.
     Back in the summer of 1936, I was an 8-year-old kid growing up in north central New Jersey. There was quite a bit of aviation history being made in that part of the country, and my home town was situated about 14 miles from Newark Airport, at that time the commercial gateway airport for New York City (La Guardia and JFK came later), and Hadley Field, the eastern terminus for the transcontinental air mail system. My older brother and I were kind of the air-minded kids in the neighborhood, and quite often in the summer, the family Sunday drive would end up at Hadley Field. On Sunday afternoons in summer, Hadley usually featured barnstorming rides in a tough old biplane, the New Standard D-25, which was owned by the airport manager and fixed base operator, one Ken Unger. The New Standard was built in Paterson, N.J., as a dual purpose airplane. Powered by one Wright J-5 and flown by a single pilot out in the breeze, it featured a large compartment forward of the pilot large enough to carry 900 lbs of mail, or four passengers in two rows of two, sitting on 2x10s and strapped in with shared seatbelts. This particular Sunday, my dad announced that he was ready to spring for the $3 so that he, my brother, and I could take our first airplane ride in the New Standard. Our turn to go came pretty quickly, and over the protests of my mother and grandmother, we climbed aboard and taxied away. I don’t recall the pilot, but it was not Unger himself. I believe that he was the owner, but there was another fellow named Decker who flew for Unger a lot, so maybe he was the pilot. I do remember that it had unequal span orange wings, and a bright green fuselage, no engine cowl, and orange tail surfaces.
     Hadley had an asphalt tarmac between three or four hangars, but no paved runways, just 2,500 ft. of mowed, gently rolling grass hills that allowed takeoffs in any direction required by the prevailing wind. I don’t remember too many details of the flight, but I knew right then that I was going to be involved . . . 


New Standard D-25 NC930V


Way Back When - The Verville Air-Coach

    This series focuses on sales literature that prompted light aircraft during the Golden Age of American aviation. It will illustrate sales and marketing messages for popular, and not so well known, aircraft from the 1920s and 1930s, illuminating insight into the perspectives associated with the aviation industry of that era. 


Verville Air-Coach brochure

Forum of Flight

     The FORUM is presented as an opportunity for each member to participate in the Journal by submitting interesting or unusual photographs. Negatives, black-and-white or color photos with good contrast may be used if they have smooth surfaces. Send submissions to the Editorial Committee marked "Forum of Flight," P.O. Box 3023, Huntington Beach, CA 92605-3023. Mark any material to be returned: "Return to (your name and complete address)."

     Please include as much information as possible about the photo such as: date, place, names, etc., plus proper credit (it may be part of your collection but taken by another photographer).


Vought SU-1, BuNo 8931, damaged at Logan Airport, Boston, MA


News & Comments / President’s Message

     Additions, corrections and general comments from AAHS members and other individuals that have contact the Society. 
     The President's Message contains the Society's management perspective on the current status of the Society was well as directions and initiatives that the organization is pursuing.
     Members are encourage to let headquarters know their thoughts and suggestions for helping the Society achieve its services and educational goals.