Martin SC-1

 

The Curtiss CS (or Model 31) was a reconnaissance and torpedo bomber aircraft used by the United States Navy during the 1920s. It was a large single-engine biplane with single-bay unstaggered wings, the design conventional in all respects other than that the lower wing was of greater span than the upper. The CS was built to allow its undercarriage to be quickly and easily interchangeable between wheeled, tailskid undercarriage, and twin pontoons for operation from water. Provision for the carriage of a torpedo was semi-recessed into the underside of the fuselage, blended in behind an aerodynamic fairing. The pilot and gunner sat in tandem open cockpits, while accommodation inside the fuselage was provided for a third crewmember who served as bombardier and radio operator. This station was also provided with a dorsal hatch aft of the gunner's position, and a ventral blister aft of the torpedo recess, which was used for aiming bombs or torpedoes.

 

The aircraft was originally designed by the Navy Bureau of Aeronautics. Curtiss won the contract to produce this aircraft, which became the Curtiss CS in the 1922-23 system, standing for Curtiss Scout.

 

 

First flying in 1923, Curtiss produced six CS-1 prototypes for the Navy in 1923powered by 530 hp (395 kW) Wright T-2 engine, which were mostly used for engine tests. Two examples of the improved CS-2 improved version with 600 hp (448 kW) Wright T-3 engine and more fuel were built the following year and set a number of world speed, distance, and endurance records for seaplanes in its class. They were delivered in April 1924 and served with Squadron VT-1. The CS-2 were one converted from CS-1 and two new-built aircraft by Curtiss.

 

The Navy ordered both the CS-1 and CS-2 into production, but when Curtiss tendered with a price of $32,000 per aircraft, Martin undercut them with a tender of $25,200 for each CS-1 and $19,863 for each CS-2 and won the contract. Curtiss refused to provide full sets of drawings and data to Martin, so Martin-built machines were in part reverse-engineered from a Curtiss-built CS-1 provided by the Navy. These aircraft entered service with squadrons VT-1, VT-2 and VS-1. By the time the Martin-produced aircraft were delivered in 1925–26, the Navy's designation system had changed, and they entered service as the SC-1 (35 built) and SC-2 (40 built). Martin-built SC-2s suffered from poor handling characteristics and soon earned the nickname "Sea Cow". The Martin T2M was an alternative designation for the Martin built SC series. Meanwhile, the Naval Aircraft Factory made extensive modifications to the two Curtiss CS-2s leading them to be re-designated CS-3. Curtiss modified a CS-2 with a geared engine, as the CS-3, which formed the basis of the Martin T3M. The Martin XSC-6 was a conversion of an SC-1 with a 730 hp (545 kW) Packard 1A-2500 engine.

 

 

Further development of the design was carried out by Martin as the T3M and T4M building 124, and eventually by Great Lakes as the TG.

 

The XSC-7 was a conversion of a CS-1 with a T-3A engine and increased gross weight.

 

In all. 83 were built.

 

In 1924, the CS-2 was used to break numerous world records for seaplanes in its class in three long-range flights. The first of these took place overnight between 22 and 23 June, when Lt Frank Wead and Lt John D. Price set five records – distance (963.123 mi, 1,544.753 km), duration (13 hours, 23 minutes, 15 seconds), speed over 500 km (73.41 mph, 117.74 km/h), speed over 1,000 km (74.27 mph, 119.12 km/h) and speed over 1,500 km (74.17 mph/118.96 km/h).[1] Between 11 and 12 July, the same pilots would break the distance and duration records again (994.19 mi/1,594.58 km over 14 hours, 53 minutes, 44 seconds).[1] On October 10, these same two records would be exceeded by Lt Andrew Crinkley and Lt Rossmore Lyon in a flight of 1,460 mi (2,342 km) in 20 hours, 28 minutes. While these would have been new world records, the flight was not officially timed, and was therefore not recognized as such.

 

 

On September 23, 1925, the U.S. Navy flew 23 Curtiss CS-1 floatplanes to Bay Shore Park on the Chesapeake Bay, 14 miles SE of Baltimore, Maryland, on a Friday with the intention of an air show demonstration before the 1925 Schneider Cup Race on Saturday, but that night gale-force winds broke three-inch mooring and anchor ropes on 17 of the biplanes and they were blown onto shore or dashed against seawalls, destroying seven and damaging ten. The next afternoon's Baltimore Evening Sun had the headline "Plane Disaster in Harbor Called Hard Blow to Navy" and quoted General William "Billy" Mitchell, who called the loss of the CS-1s "staggering" and blamed it on Navy mismanagement of its aviation program.

 

By the middle of 1927 CS/ SC were still in use with VT-2B, which had a mix of the Martin produced SC-1s and SC-2s. In addition they were used by VN-3D8 training squadron at Pensacola, which operated 15 SC-1s and 15 SC-2s.

 

 

Curtiss CS-1

Engine: 525hp Wright T-2

Crew: 3

6 built

 

Curtiss CS-2

Engine: Wright T-3

2 built

 

Martin SC-1

35 built

 

Martin SC-2

Engine: Wright T-3, 585 hp (436 kW)

Wingspan: 56 ft 7 in (17.25 m)

Wing area: 856 sq ft (79.5 sq.m)

Length: 37 ft 9 in (11.51 m)

Height: 14 ft 8 in (4.47 m)

Empty weight: 5,007 lb (2,271 kg)

Gross weight: 8,422 lb (3,820 kg)

Maximum speed: 103 mph (166 km/h; 90 kn) at sea level

Range: 1,018 mi (885 nmi; 1,638 km)

Service ceiling: 8,000 ft (2,400 m)

Time to 2,000 ft (610 m): 10 minutes

Armament: 1 × rearward-firing machine gun in ring mount

Bombload: 1 × 1,618 lb (734 kg) torpedo

Crew: 3

40 built

 

Martin CS-3

CS-2 conversion

Engine: geared Wright T-3

 

CS-4 / CS-5

Naval conversions

 

XSC-6

Martin SC-1 (A6835)

Engine: 730hp Packard 1A-2500

 

SC-6

The second Martin SC-1 (A6824)

Engine: Packard 1A-2500

 

XSC-7

Single Curtiss CS-1 conversion

Engine: T-3A