Douglas A/B-26 Invader

Prototypes - L.B. Smith Aircraft Corporation

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L.B. Smith Aircraft Corporation


Based in Miami, Florida, this company specialized in conversions of the C-46 and C-82 aircraft as well as producing airliner interior components.


Founded in 1947 at Miami Intl. Airport by company president L.B. Smith, it quickly became one of the foremost aircraft conversion, overhaul and modification centers in the United States. They did executive aircraft interiors for many types from the Douglas DC-3 to the Lockheed JetStar.

Their most famous conversions were ex-military Douglas A-26 Invaders known as the Smith Tempo II executive transports and the Curtiss C-46 Commando which became the Smith "Super 46". Seven or more C-82 Packets were briefly acquired by L.B. Smith in 1955 where they were de-militarized for civilian service in Latin America. L.B. Smith was closely associated with a similar company called Aerodex Inc., who was a  CAA approved aircraft repair station.

The seven seat Super 26, made its first appearance at the National Business Aircraft meeting in Philadelphia in the late ‘50s. The aircraft cruised at 325 m.p.h. on 60 per cent power, and had a range of 2,100 miles at a take-off gross weight of 35,000 lb.


The company then decided to completely re engineer the Invader and replaced both spars with ring spars built of aluminium. This also saw a spread of the wing center section which moved the wings and engines 20 inches outboard from the cabin on each side to reduce noise. The aircraft, like the On Marks, received DC-6 wheels and brakes, new canopy and cockpit, lengthened nose, rebuilt fuselage, and numerous other modifications. Named the Biscayne 26, it is thought that only one aircraft was built before the company decided to start with a clean sheet of paper.


The new aircraft would have a completely new and much larger fuselage that would ultimately be pressurized.

Two variants were to be offered, the Tempo I ( unpressurized ) and the Tempo II ( all options included and was to be pressurized ). The Tempo series was nearly ten feet longer than a standard Invader and because of the ring spars and had a 28-foot stand-erect cabin that could accommodate up to 13 passengers.

Everything else on the first Tempo II was completely modernized and was an impressive aircraft, making its first flight as N4204A during October 1959.

The new interior of the machine was designed by Charles Butler Associates in a color scheme featuring gold, wheat and tones of blue. "Cabinetry is of smooth, hand-rubbed blond walnut," and "the instrument panel and overhead panel was finished in turquoise with eyebrow type lighting”.

Price was to be a reasonable $375,000 but it appears only two were built. The first one eventually went to the University of Nevada conducting atmospheric research for over a decade and was lost over the Sierras when it crashed due to extreme airframe icing. The second, registered N4214A, eventually went to Mexico registered XB-ZOA, with the current status unknown.




I had a great email from Charles Stevens on 13th December 2014, it reads:

I wish to thank you for the terrific story on the L. B. Smith Tempo II aircraft. I worked for Smith in Miami
between 1954 and 1961. I was the electrical/instrument designer on the Tempo. I also designed the cockpit
layout and panels. I was also part of the test flight crew and spent many hours in the aircraft.

I would like to have a photo of the plane if you have one that you could scan and e-mail me.

If you have any questions please ask, I will be happy to answer if I can.
Charles Stevens
Charles continues:

This is my recollection of the design, building and flying of the L. B. Smith Aircraft company’s Tempo II heavily modified A/B 26 Invader at the cantilevered Smith hanger on the NW corner of the Miami International airport during the late 1950’s and early 1960’s.

The general manager of the facility was a Mr. Bellomy (sic). There were many people that put in a lot of time to make this very fine propeller driven 13 passenger corporate aircraft. The chief engineer Mr. Brush, project engineer Jack, I forgot his last name, electrical engineer John Ewbanks, mechanical stress engineer Mr. Simmons, , electrical designer Charles Stevens (myself) and all of the shop workers.

Mr. Simmons was the one who developed the wing ring spars and was not only responsible for the stress testing of the spars but actually conducted the test in the shop.

The A/B 26 airframe was bought into the facility, the empennage and tail surfaces, wings and nose wheel well were removed and saved while the rest of the airframe was discarded. The nose wheel well was mounted on the fuselage jig and then the completely new fuselage was built around it. The empennage was split and expanded to match the height of the new fuselage. The wing ring spars were 4 aluminium plates that served as the anchors for the wing mounting.

There was an opening in the middle of these ring spars that allowed for a person to pass through for ingress and egress to the cockpit. The fuselage was high enough for a six foot man to walk throughout the cabin and through to the cockpit. There was an electronic bay between the two sets of spars where most of the equipment was located. The luggage compartment was located in the middle of the extended nose with radar in the nose and two large inverters located behind the luggage area. The cabin accommodated 13 passengers and was pressurized for flight at, I believe, 28,000 ft. It had a full galley.

The first test flight was a skip flight down the runway just to see if it would fly, when it was rolled out for this flight it looked like a ruptured duck. The tail hung down as if it was tail heavy. They brought it in from the flight and before it flew again one frame length of the fuselage was removed which made it sit level.

Between the first flight and the second a fancy paint job was applied and when it cleared the hanger to where the control tower could see it the tower spoke up with “My! It sure is pretty, do it fly?”

Most of the test flights were, of course, normal, no problem, however, there were some harry ones. Early on, a hydraulic line in the right wing root seemed to keep splitting. I happened to be on one of those, I was riding the photo panel in the cabin, we were doing saw toothed climbs for generator cooling  when I looked through the window and saw red fluid coming off of the right nacelle, told the pilot, he said come on up we have to get home. When we landed we had no steering so the pilot and co-pilot tried to steer using engine speed and prop reversing to the point that we ended off the taxiway and in the field. No excitement just inconvenient.

On one of the flights, they were doing saw tooth climbs at 18,000, single engine and the plane would not stall off, it just sorta floated around and then it went off one wing, went inverted. The pilots fought it and finally recovered at 8,000. The strange thing is, the person riding the photo panel never knew they were inverted until we went through debrief and he saw the horizon go inverted. You’re right, that is a drop of 2 miles.

On another flight, again doing single engine parameter, the engine split a exhaust so that the heat was hitting the firewall opposite the engine electrical box and proceeded to burn through the firewall. They began to lose engine instruments, 1st the BMEP, not critical; 2nd don’t remember, but 3rd was the oil pressure. They reduced power, started the cold engine and hoped it would get warn before they need power out of it. As it worked out, the engine with the fire froze in air, and the second froze after landing. This is as I remember it. Though the root cause was the split exhaust, the fire detection failed to detect the fire because the detector was too big to fit into where the flame was. This prompted a replacement of the fire detection system with one that was smaller.

On yet another test flight just before the New York City air show they found that when they were pressurized at altitude things were normal but when they began to descend the cabin pressure would cycle from +1000fpm to -1000fpm.

Since I was designer for instrument systems it fell to me to go on the flight to analyse the problem. We went to 18,000 just off shore from West Palm Beach headed south. As soon as we started our descent and speed started to build the cycling started. We thought that it was a function of speed, so back to altitude, we increased power in the level, I was taking instrument readings Alt., OT and speed. Our top indicated speed was 420, I don’t remember OT but there was no cycling. We analysed the problem to be not enough dead band in the duct pressure sensor setting and that it was probably an attitude situation for air entering the intake. When we did debrief when we got back Mr. Bellomy slid back from his desk, pulled out a flight computer and said “Gentlemen, I don’t know if you thought about it but you were truing at 510?” We adjusted the dead band and on the flight to the air show there was no cycling on let down in NYC.


Martin, I hope this gives you something to work with, if you have any questions feel free to

e-mail or if you want and it can’t wait, call. If I think of any more interesting points I will write you.


Additional info:

I asked Chuck if he had any photos or documentation during his time at Smith's

No, I didn't save anything, it was 53 years ago and if I had, it probably would be lost by now with all of the moves I've made. Sorry about that but I guess the only things saved are memories. My job at Smith was my most favourite, I got to be around aviation and was paid for it.

Just a little about me. In the 1940's I lived in a small farming town and devoured books that included any thing about
aviation. My family lived about 4-5 blocks from the town airport and I would spend a lot of time there, talking to the local duster and barnstormers with their jennies that had been converted to crop dusters. The field was loose rock and often when landing they would kick up a rock through the wing surface. They would use a circular needle to stitch a patch in place and then dope it up all the time telling stories about their flying.

With this background when I graduated high school and got married had 2 children, I had to go to work with no training I was stuck in jobs like truck driving, maintenance and other low pay jobs. Then in 1952 I enlisted in the Marine Corp, had my basic in Paris Island Boot Camp, while there I was called into the Battalion CO's office and was asked "Just what the hell was a man with 2 children doing enlisting in the Marine Corp during wartime." I told him I wanted to get training in aviation. After boot I was assigned to airman prep (AP) school in Jacksonville, Florida. After AP school I was assigned to Aviation Electrician (AE-A) school also in Jacksonville. I graduated top student in that school and then was asked to stay as an instructor. I taught electrical theory, troubleshooting theory and finished my assignment teaching practical troubleshooting on real aircraft. Except for the military side it was great duty. I left the military in 1954.

After the military I went to work at L. B. Smith working there until 1961. I started as a Class C electrician. Due to my troubleshooting ability I was rapidly promoted through Class B to Class A. One day my boss, John Kelley, asked if I could do drafting, since I had in high school I said yes and so became the electrical draftsman and then started designing electrical circuits for corporate aircraft and then for the C-46 line. I was later made lead electrician on the corporate line. In 1957, due to a disagreement with my boss's boss I threatened to quit. The Chief Engineer Mr. Brush called me in and offered me the position of Electrical Designer. Of course, I jumped at it. The most complex circuit that I designed in the Tempo aircraft was the prop reversing circuit. No one in the shop could troubleshoot it so I had to.

I hope this isn't too much.


To a Buddy with similar interest!


God Speed and Merry Christmas,

Charles Stevens

Bluffton, Indiana


Smith Super 26

Standard Invader airframe converted with wingtip tanks and an executive interior.


Smith Biscayne 26

A high-speed transport version developed by the L.B. Smith Company and able to seat nearly twice that of the Super 26. It is believed that the same airframe ( 44-35640 ) was used as the base for this and future conversions performed by the company, eventually evolving into the Tempo I and II.

The Biscayne 26 brochure


Smith Tempo I

Unpressurised executive conversion with R-2800 B series engines and a new fuselage which was 9 ft 7 1/2 in (2.93 m) longer than the standard and able to seat up to 13 passengers. Both spars were replaced with ring spars built of aluminium. The opening of the wing center section mounted the wings and engines outboard 20 inches away from the cabin centerline on each side, reducing noise and opening up the interior resulting in a 28-foot stand erect cabin. The aircraft, like the On Mark conversions, received DC-6 wheels and brakes, new canopy and cockpit, lengthened nose, restructured fuselage, tapered wingtip fuel tanks, and numerous other modifications.

Smith Tempo II

 The Tempo I conversion with the new fuselage was strengthened further to withstand the structural loads of pressurization. Everything else on the first aircraft was completely upgraded and refined, including new R-2800 C series engines. It was a massive yet sleek aircraft, making its first flight as N4204A during October 1959. The price was set at $375,000 but it appears only two were built. The first one eventually went to the University of Nevada and was lost over the Sierras when it crashed due to extreme airframe icing while performing atmospheric testing.

There was no indication of structural or equipment failure contributing to the crash.


( See accident report Ref. NTSB LAX-80-F-A060 for N4204A, along with more information for N4204A and N4214A )



The above two shots show Tempo II N4204A as she appeared in her " Prototype " Display paint scheme, circa 1960.
They are taken from the May 1960 issue of Flying Magazine " Flying News Reel " section ( page 52 ). Permission to scan and use these images came from J. Mac McClellan, Editor-In-Chief, Flying Magazine. He is being Cc'd on this mail, along with Graham.


Regarding the above photograph, Rick writes:
This is the one that I referred to when our association began back in 2009 that appeared in an issue of Air Progress magazine. If memory serves, it was the Fall of 1959 issue and was referred to as the latest modified B-26 Invader by L. B. Smith as the Tempo II. This is the only photo I have ever seen of the Tempo II in this scheme and would predate the one I referred to as the “ Prototype – Demonstrator “ scheme ...





Regarding the above imageS and illustration: These images were from the 1960 timeframe and was how she appeared referenced in advertising and news listings in Flying magazine in May of 1960 and other issues. It was also as she appeared at the N.B.A.A. ( National Business Aviation Association ) airshow at Reading Pennsylvania.
Based on the colors indicated in the brochure and the above color photo was what I used to make up my profile drawings of the “ Prototype – Demonstrator “ scheme. I also made up a new set using these colors and labeled it as the “ Early Prototype scheme “ ( first ). I did a single profile drawing and a dual profile showing the fuselage only together with a full left-side profile. Because L. B. Smith used blue-green and blue in various shades for both N4204A and N4214A over time I feel that it reasonable to assume these closely represent how N4204A appeared in early 1959. The scheme and hues are as close as I could get from the angle shown in that first rare B & W photo image.




Prototype serial number: 44-35640





Second prototype Serial number: 44-34127 - N4214A


Editing and updates by Richard E. Fulwiler, 2 August, 2011

Associated reading

A Tuskegee Airman

Joseph T. Camilleri, a Brooklyn native who attended Harren Aviation High School in Manhattan, Camilleri started flying in 1933 at Floyd Bennett Field in New York City. Because of his Naval Air Reserve training, Camilleri was to become the first instructor for the famed Tuskegee Airmen.

"In 1940, due to my qualifications. I was summoned to Tuskegee Institute, Alabama to initiate a flight and ground school training program," he said. Camilleri took on the task of training young, eager Black cadets at a time when it was not fashionable for a Yankee from the North to associate with people of color in the South. Camilleri's initiation of this flight program would later help train such noted Tuskegee Airmen as Benjamin O. Davis, Jr., Spann Watson, Hannibal Cox, Willie Fuller, Leo Gray and others. He was to stay in Tuskegee about a year before reporting to Wilmington Air Force Base in Delaware. Enjoyable tenure at Tuskegee was interrupted when I was summoned to active duty," he said.

Camilleri was to stay in the armed forces until 1946, leaving with the rank of captain. After this, he came to Miami to live and fly. Here he initially owned and operated three non-scheduled airlines, flew as a test pilot for L.B. Smith Services and started an aircraft maintenance base at Miami International Airport. In 1971 he started Electra Aircraft Parts, Inc. which he owns today. Camilleri is a charter member of the local chapter of the Tuskegee Airmen, Inc. Camilleri helped train Benjamin O. Davis Jr., Spann Watson and others.

Editing and updates by Richard E. Fulwiler, 2 August, 2011