Daily Archives: October 23, 2021

23 October 1959

American Airlines’ first Boeing 707-123 airliner, N7501A, is rolled out. (Boeing)

23 October 1959: American Airlines accepted delivery of its first jet airliner, Boeing 707-123 N7501A (serial number 17628, line number 7). The new airplane had made its first flight on 5 October. Christened Flagship Michigan, American Airlines advertised its new 707 as the “Astrojet.”

The Boeing 707 was developed from the earlier Model 367–80, the “Dash Eighty.” It is a four-engine jet transport with swept wings and tail surfaces. The leading edge of the wings are swept at a 35° angle. The airliner had a flight crew of four: pilot, co-pilot, navigator and flight engineer. The airliner could carry a maximum of 189 passengers.

The 707-123 was 145 feet, 1 inch (44.221 meters) long with a wing span of 130 feet, 10 inches (39.878 meters). The top of the vertical fin stood 42 feet, 5 inches (12.929 meters) high. The 707 pre-dated the ”wide-body” airliners, having a fuselage width of 12 feet, 4 inches (3.759 meters). The airliner’s empty weight is 122,533 pounds (55,580 kilograms). Maximum take off weight is 257,000 pounds (116,573 kilograms).

Boeing 707-123 N7501A, American Airlines Astrojet, Flagship Michigan, at Seattle. (American Airlines)

The first versions were powered by four Pratt & Whitney Turbo Wasp JT3C-6 turbojet engines, producing 11,200 pounds of thrust (49,820 kilonewtons), and 13,500 pounds (60.051 kilonewtons) with water injection. This engine was a civil variant of the military J57 series. It was a two-spool axial-flow turbojet engine with a 16-stage compressor and 2 stage turbine. The JT3C-6 was 11 feet, 6.6 inches (3.520 meters) long, 3 feet, 2.9 inches (0.988 meters) in diameter, and weighed 4,235 pounds (1,921 kilograms).

At MTOW, the 707 required 11,000 feet (3,353 meters) of runway to take off.

The 707-123 had a maximum speed of 540 knots (1,000 kilometers per hour). It’s range was 2,800 nautical miles (5,186 kilometers).

In 1961, N7501A was upgraded to the 707-123B standard. This included a change from the turbojet engines to quieter, more powerful and efficient Pratt & Whitney JT3D-1. The JT3D-1 was a dual-spool axial-flow turbofan engine, with a 2-stage fan section, 13-stage compressor (6 low- and 7 high-pressure stages), 8 combustion chambers and a 4-stage turbine (1 high- and 3 low-pressure stages). This engine was rated at 14,500 pounds of static thrust (64.499 kilonewtons) at Sea Level, and 17,000 pounds (75.620 kilonewtons), with water injection, for takeoff (2½ minute limit). Almost half of the engine’s thrust was produced by the fans. Maximum engine speed was 6,800 r.p.m. (N1) and 10,200 r.p.m. (N2). It was 11 feet, 4.64 inches (3.471 meters) long, 4 feet, 5.00 inches (1.346 meters) wide and 4 feet, 10.00 inches (1.422 meters) high. It weighed 4,165 pounds (1,889 kilograms). The JT3C could be converted to the JT3D configuration during overhaul.

The 707-123B wings were modified to incorporate changes introduced with the Boeing 720, and a longer tailplane installed.

N7501A was sold to Tigerair, Inc., 12 April 1978. It was then sold to Cyprus Airways in March 1979, and reregistered 5B-DAM. When landing at Bahrain International Airport, 19 August 1979, the airliner’s nose wheel collapsed and it was damaged beyond economical repair.

Boeing 707-123B 5B-DAM (s/n 17628) at Bahrain International Airport after sustaining damage when its nose wheel collapsed on landing, 19 August 1979. (Steve Fitzgerald/Wikimedia Commons)

The Boeing 707 was in production from 1958 to 1979. 1,010 were built. Production of 707 airframes continued at Renton until the final one was completed in April 1991.

© 2018, Bryan R. Swopes

23 October 1934

Warrant Officer Francesco Agello, Regia Aeronautica. (FAI)
Warrant Officer Francesco Agello, Regia Aeronautica. (FAI)

23 October 1934: At Lago di Garda, Brescia, Italy, Warrant Officer Francesco Agello, Regia Aeronautica, set a Fédération Aéronautique Internationale (FAI) World Record for Speed Over a 3 Kilometer Course when he flew the Macchi Aeronautica M.C. 72 float plane, serial number MM 181, to an average speed of 709.21 kilometers per hour (440.68 miles per hour).¹

A contemporary news article described the event:

FLYING the Machi-Castoldi 72 seaplane (3,000 h.p. special 24-cyl. Fiat) at Lake Garda on Tuesday of last week, Warrant-Officer Francesco Agello, of the Italian Royal Air Force, raised his own world’s air speed record by putting up a mean speed (subject to homologation) of 709.202 km./hr. (440.677 m.p.h.) for the usual four flights. His previous record stood at 682.403 km./hr. (423.76 m.p.h.)

The weather conditions under which the attempts were made were ideal, there being just sufficient breeze to take the glassiness off the water, so assisting the takeoff. Temperature was suitable, and the air was free from bumps.

Just before 3 p.m. Agello took off and made four runs over the three-kilometre course, clocking as follows:—

[Direction]         Secs.               km./hr.          m.p.h

North-South     15 29/100        705.882        438.614
South-North     15 19.2/100     710.433        441.423
North-South     15 18.1/100     711.462        442.081
South-North     15 23.4/100     709.034        440.738

Warrant Officer Francesco Agello with his Macchi M.C.72. (FAI)
Warrant Officer Francesco Agello with his record-setting Macchi M.C.72, MM 181. (FAI)

After the successful attempt a banquet was held in the Officers’ Mess at Desenzano in Agello’s honour. The speeds were announced, and Col. Bernasconi, who is in command of the High-speed Flight, stated that Signor Mussolini had honoured Warrant-Officer Agello by promoting him to a full lieutenant.

Only a few modifications had been made to the Macchi-Castoldi since the previous attempt, chief among them being the substitution of wooden floats for the metal ones previously used.

Illustration of the Fiat AS.6 V-24 aircraft engine, right side.
Illustration of the Fiat AS.6 DOHC V-24 aircraft engine, right side. (Old Machine Press)

As is well known. the most interesting feature of the machine is the extremely unconventional power-unit, the Fiat A.S.6. The problem of frontal area for such a powerful unit as was specified was solved by placing the twenty-four cylinders (totalling in capacity over fifty litres) in two rows, forming a 60 deg. “vee,” and further, arranging them in two mechanically independent groups.

Each group has its own crank shaft, but a single crank case is used for both. The crank shafts, which rotate in opposite directions, are coupled in the centre by spur-gear reduction units, which drive two airscrew shafts. One of these shafts is hollow, and the other operates within it. The two shafts run forward through the “vee” of the front unit, and each carries an airscrew; so that there are two of the latter, close together, but revolving in opposite directions.

Each engine unit has independent camshafts (two per engine), water pump and dual Marelli magnetos, but a common induction system is used, an eight-jet carburetter being mounted behind the rear unit and mixture being drawn from it passed to the cylinders by a supercharger geared up to 20,000 r.p.m. An interesting point is that this supercharger absorbs 200 h.p., and, since it is driven by the rear engine, the blades of the front airscrew (which the rear engine drives) are given different inclination to correct for the slight difference in power.

The power units develop 3,000 h.p. at 3,200 r.p.m., and weighs 2,045lb., giving a weight per h.p. of 0.706lb. The all-up weight of the machine, with pilot and full tanks, is 6,670lb.

British equipment figured in the success, for Castrol oil and K.L.G. plugs were used.

FLIGHT, The Aircraft Engineer and Airships, No. 1349, Vol. XXVI, November 1, 1934, at Page 1152.

Warrant Officer Francesco Agello, Regia Aeronautica, with the record-setting Macchi M.C.72, 23 October 1934.
Warrant Officer Francesco Agello, Regia Aeronautica, with the record-setting Macchi M.C.72, 23 October 1934. (Historic Wings)
Left rear quarter view of the Macchi M.C.72. (FAI)
Left rear quarter view of a Macchi M.C.72. (FAI)

The Macchi-Castoldi M.C.72 was designed by Mario Castoldi for Aeronautica Macchi. It was a single-place, single-engine, low-wing monoplane float plane constructed of wood and metal. It was 8.32 meters (27 feet, 3.5 inches) long with a wingspan of 9.48 meters (31 feet, 1.25 inches) and height of 3.30 meters (10.83 feet). The M.C.72 had an empty weight of 2,505 kilograms (5,512 pounds), loaded weight of 2,907 kilograms (6,409 pounds) and maximum takeoff weight of 3,031 kilograms (6,669 pounds).

It was powered by a 50.256 liter (3,067 cubic inch) liquid-cooled, supercharged Fiat S.p.A. AS.6 24-cylinder 60° dual overhead cam (DOHC) V-24 engine with 4 valves per cylinder. The engine produced 3,100 horsepower at 3,300 r.p.m. and drove two counter-rotating metal two-bladed fixed pitch propellers with a diameter of 8 feet (2.56 meters). The counter-rotating blades cancelled the torque effect of the engine.

Surface radiators were placed on top of each wing and surface oil coolers on the floats.

Radiators were placed on the upper surface of each wing. (Aeronautica Militare)
Radiators were placed on the upper surface of each wing. (Aeronautica Militare) 
The Henry De la Vaulx Medal.
The Henry de la Vaulx Medal.

Five Macchi M.C.72 float planes had been built for the 1931 Schneider Trophy race, but problems with the Fiat AS.6 engine, which was essentially two AS.5 V-12s assembled back-to-back, prevented them from competing.

Four test pilots, including Francesco Agello, had been selected to fly the airplanes for speed record attempts. Two were killed while testing the M.C.72, and the third died when another airplane crashed. The cause of the accidents were explosions within the engines’ intake tract. Though they ran perfectly on test stands, in flight, they began to backfire, then explode.

It was discovered by Rod Banks, a British engineer who had been called in to develop a special high-octane fuel, that the Fiat engineers had overlooked the ram effect of the 400 mile per hour slipstream. This caused the fuel mixture to become too lean, resulting in predetonation and backfiring. A modification was made to the intake and the problem was resolved.

Macchi M.C.72 at Aeronautica Militare
Macchi M.C.72 MM 181 at the Museo Storico dell’Aeronautica Militare (Italian Air Force Museum) in Vigna di Valle, Italy. (Unattributed)

Francesco Agello was twice awarded the Henry De La Vaulx Medal by the Fédération Aéronautique Internationale, and also awarded the Medaglia d’oro al valore aeronautico. In part, his citation read, “A high speed pilot of exceptional courage and, after competition in difficult and dangerous test flights during the development of the fastest seaplane in the world, twice he conquered the absolute world speed record.”

Captain Agello was killed in a mid-air collision, 26 November 1942, while testing a Macchi C.202 Fogore fighter.

Medalglia d'oro al valore aeronautico
Medalglia d’oro al valore aeronautico

¹ FAI Record File Number 4497

© 2016, Bryan R. Swopes

23 October 1911

Captain Carlo Piazza in the cockpit of his Blériot XI. (Aeronautica Militaire Italiana)
Capitán Carlo Piazza in the cockpit of his Blériot XI. (Aeronautica Militaire)
Capitán Carlo Piazza
Capitán Carlo Maria Piazza (1871–1917)

23 October 1911: For the first time, the airplane is used in warfare. Capitán Carlo Maria Piazza, a pilot commanding an aviation unit of the Regio Esercito (the Italian Royal Army), flew a Blériot Type XI on a reconnaissance mission over the Zanzur oasis, south west of Tripoli, Libya, during the Italo-Turkish War (1911–1912).

Aviation author Walter J. Boyne wrote that, “The world’s first combat flight took place on October 23, when the Commander of the Air Fleet, Captain Piazza, took off at 6:19 a.m. to reconnoiter Turkish positions. In a sixty-one minute flight, he discovered several enemy encampments. . . .”

The Influence of Air Power Upon History, Walter J. Boyne, Pen & Sword Books Limited, 2005, at Page 37.

Capitán Piazza with a Blériot XI, Tripoli, Libya, 17 February 1912.

The Blériot XI was a single-seat, single-engine monoplane, designed by Raymond Saulnier and built by Louis Charles Joseph Blériot. It was 24 feet, 11 inches (7.595 meters) long with a wingspan of 27 feet, 11 inches (8.509 meters) and overall height of 8 feet, 10 inches (2.692 meters). It had an empty weight of 507 pounds (229.9 kilograms).

(Sources give conflicting specifications for the Blériot XI, probably because they were often changed in an effort to improve the airplane. Dimensions given here are from the three-view drawings, below.)

(Flight, No. 149., Vol. III, No. 44, 4 November 1911, at Page 967)

In its original configuration, the Type XI was powered by an air-cooled, 3.774 liter (230.273 cubic inches) Robert Esnault-Pelterie (R.E.P.) two-row, seven-cylinder fan engine (or “semi-radial”), which produced 30 horsepower at 1,500 r.p.m., and drove a four-bladed paddle-type propeller. The R.E.P. engine weighed 54 kilograms (119 pounds). This engine was unreliable and was soon replaced by an Alessandro Anzani & Co. W-3.

The Blériot XI Militaire was powered by a normally-aspirated, air-cooled, 7.983 liter (487.140-cubic-inch-displacement) Société des Moteurs Gnome Omega 7-cylinder rotary engine which produced 50 horsepower at 1,200 r.p.m. The direct-drive engine turned a two-bladed wooden propeller in a left-hand, tractor configuration. The Omega 7 is 79.2 centimeters (2 feet, 7.2 inches) long, 83.8 centimeters (2 feet, 9.0 inches) in diameter, and weighs 75.6 kilograms (166.7 pounds). The prototype of this engine is in the collection of the Smithsonian Institution National Air & Space Museum.


Blériot Type XI, front view.
Blériot Type XI, side view.
Blériot Type XI, top view.

The Blériot XI had a maximum speed of 76 kilometers per hour (47 miles per hour) and its service ceiling was 1,000 meters (3,281 feet).

Captain Piazza was killed in action in 1917, during the First World War.

A two-place Blériot Type XI at Il Museo Storico dell’Aeronautica Militare. (Museo Storico A.M.)

© 2018, Bryan R. Swopes