Tuesday, December 27, 2005
Steve's Video Of The Day: Grumman Mallard "Plunge"!
On Dec. 19, a Chalk's Ocean Airways aircraft, a Grumman G-73T Turbo Mallard crashed after take-off from the water at Miami Beach, Florida. It was a tragic happening, with all 20 people aboard perishing. It appeared that one wing separated in flight, and the aircraft plummeted to the ocean. The aircraft was built in 1947. The accident ends a historic run for Chalk's Ocean Airways, which claims to be the oldest US airline and one that has never had a fatal crash with passengers on board. The airline got its start in 1919. Chalk's owns 4 other Mallards, and has voluntarily grounded them all for inspection.
Aviation lore has it that the airline profited and grew from running-rum during Prohibition, and then gained fame in the 1930s shuttling personalities between Miami and the Bahamas. Apparent famous passengers included Al Capone, Judy Garland, and Howard Hughes.
VIDEO - Grumman Mallard "Plunge"!
***NTSB releases pictures of crashed Mallard fatigue cracks***
The NTSB's caption to the picture above reads: "Overall view of the inboard end of the right wing as it was recovered from the water. A labeled arrow indicates the lower spar-cap of the rear spar where fatigue features were observed."
The NTSB captions this picture: "Closer view of the fracture surface at the inboard end of the lower spar-cap of the right wing rear spar. Unlabeled arrows indicate the location of two offset drilled holes."
Concerning this picture, the NTSB says: "Closer view of the fatigue region in the horizontal leg of the lower spar-cap of the rear spar. Unlabeled brackets indicate fatigue origin areas at the surfaces of the fastener hole, and dashed lines indicate the extent of the fatigue region visible on the fracture surface."
GRUMMAN G-73 MALLARD
Country of origin:
United States of America
Powerplants:
G73 - Two 450kW (600hp) Pratt & Whitney R1340S3H1 Wasp nine cylinder piston radial engines driving three blade constant speed propellers. G73T - Two 530kW (715shp) Pratt & Whitney Canada PT6A27 or PT6A-34 turboprops.
Performance:
G-73 - Max speed 346km/h (187kt), cruising speed 290km/h (157kt). Initial rate of climb 1290ft/min. Service ceiling 23,000ft. Range with max fuel 2220km (1655nm). G-73T - Max cruising speed 354km/h (191kt), economical cruising speed 346km/h (187kt). Initial rate of climb 1350ft/min. Service ceiling 24,500ft. Range with max fuel and no reserves 2595km (1400nm), with max payload and no reserves 1388km (750nm).
Weights:
G-73 - Empty 4240kg (9350lb), max takeoff 5783kg (12,750lb). G-73T - Empty equipped 3970kg (8750lb), max takeoff 6350kg (14,000lb).
Dimensions:
G-73/G-73T - Wing span 20.32m (66ft 8in), length 14.73m (48ft 4in), height on undercarriage 5.72m (18ft 9in). Wing area 41.3m2 (444sq ft).
Capacity:
Crew of two. Main cabin seating for up to 10 passengers, seating later increased. Many aircraft used as executive transports with customized interiors.
Production:
59 Mallards built between 1946 and 1951. Small numbers later converted to turboprop power.
Type:
Ten seat utility amphibious transport
History::
Following in the footsteps of the smaller Goose and Widgeon before it, Grumman developed the G-73 Mallard amphibian for commercial use.
Developed in the immediate postwar years, the Mallard is of similar overall configuration to Grumman's earlier amphibious designs in that it features twin radial engines on a high mounted wing with under wing floats, retractable undercarriage and an unswept tail unit. Unlike the earlier aircraft the Mallard features tricycle undercarriage, a stressed skin two step hull and fuel can be carried in the wingtip tanks.
The Mallard prototype first flew on April 30 1946, and the type entered service shortly afterwards in September that year with a Canadian operator. The Mallard was designed for regional airline operations with two pilots and 10 passengers, but most of the 59 delivered were for corporate use. Today only a small number remain in use, but their unique amphibious capability means they remain popular, particularly with tourist operators.
Like the earlier and smaller Goose, the Mallard has been fitted with Pratt & Whitney Canada PT6A turboprops. Frakes Aviation in the USA re-engined a small number of Mallards as G73Ts in the early 1970s, the PT6s substantially boosting performance and operating economy. The first Frakes conversion first flew in 1969 and an FAA supplemental type certificate was awarded in October 1970.
In early 1994 a plan emerged which would see the Mallard reenter production in the Czech Republic. Aero and Levov of the Czech Republic, and Duncan Aviation of the USA hoped to raise the necessary capital to restart the line in the late 1990s. These plans are believed to have been dropped.
May the crew and passengers "Rest In Peace".
Aviation lore has it that the airline profited and grew from running-rum during Prohibition, and then gained fame in the 1930s shuttling personalities between Miami and the Bahamas. Apparent famous passengers included Al Capone, Judy Garland, and Howard Hughes.
VIDEO - Grumman Mallard "Plunge"!
***NTSB releases pictures of crashed Mallard fatigue cracks***
The NTSB's caption to the picture above reads: "Overall view of the inboard end of the right wing as it was recovered from the water. A labeled arrow indicates the lower spar-cap of the rear spar where fatigue features were observed."
The NTSB captions this picture: "Closer view of the fracture surface at the inboard end of the lower spar-cap of the right wing rear spar. Unlabeled arrows indicate the location of two offset drilled holes."
Concerning this picture, the NTSB says: "Closer view of the fatigue region in the horizontal leg of the lower spar-cap of the rear spar. Unlabeled brackets indicate fatigue origin areas at the surfaces of the fastener hole, and dashed lines indicate the extent of the fatigue region visible on the fracture surface."
GRUMMAN G-73 MALLARD
Country of origin:
United States of America
Powerplants:
G73 - Two 450kW (600hp) Pratt & Whitney R1340S3H1 Wasp nine cylinder piston radial engines driving three blade constant speed propellers. G73T - Two 530kW (715shp) Pratt & Whitney Canada PT6A27 or PT6A-34 turboprops.
Performance:
G-73 - Max speed 346km/h (187kt), cruising speed 290km/h (157kt). Initial rate of climb 1290ft/min. Service ceiling 23,000ft. Range with max fuel 2220km (1655nm). G-73T - Max cruising speed 354km/h (191kt), economical cruising speed 346km/h (187kt). Initial rate of climb 1350ft/min. Service ceiling 24,500ft. Range with max fuel and no reserves 2595km (1400nm), with max payload and no reserves 1388km (750nm).
Weights:
G-73 - Empty 4240kg (9350lb), max takeoff 5783kg (12,750lb). G-73T - Empty equipped 3970kg (8750lb), max takeoff 6350kg (14,000lb).
Dimensions:
G-73/G-73T - Wing span 20.32m (66ft 8in), length 14.73m (48ft 4in), height on undercarriage 5.72m (18ft 9in). Wing area 41.3m2 (444sq ft).
Capacity:
Crew of two. Main cabin seating for up to 10 passengers, seating later increased. Many aircraft used as executive transports with customized interiors.
Production:
59 Mallards built between 1946 and 1951. Small numbers later converted to turboprop power.
Type:
Ten seat utility amphibious transport
History::
Following in the footsteps of the smaller Goose and Widgeon before it, Grumman developed the G-73 Mallard amphibian for commercial use.
Developed in the immediate postwar years, the Mallard is of similar overall configuration to Grumman's earlier amphibious designs in that it features twin radial engines on a high mounted wing with under wing floats, retractable undercarriage and an unswept tail unit. Unlike the earlier aircraft the Mallard features tricycle undercarriage, a stressed skin two step hull and fuel can be carried in the wingtip tanks.
The Mallard prototype first flew on April 30 1946, and the type entered service shortly afterwards in September that year with a Canadian operator. The Mallard was designed for regional airline operations with two pilots and 10 passengers, but most of the 59 delivered were for corporate use. Today only a small number remain in use, but their unique amphibious capability means they remain popular, particularly with tourist operators.
Like the earlier and smaller Goose, the Mallard has been fitted with Pratt & Whitney Canada PT6A turboprops. Frakes Aviation in the USA re-engined a small number of Mallards as G73Ts in the early 1970s, the PT6s substantially boosting performance and operating economy. The first Frakes conversion first flew in 1969 and an FAA supplemental type certificate was awarded in October 1970.
In early 1994 a plan emerged which would see the Mallard reenter production in the Czech Republic. Aero and Levov of the Czech Republic, and Duncan Aviation of the USA hoped to raise the necessary capital to restart the line in the late 1990s. These plans are believed to have been dropped.
May the crew and passengers "Rest In Peace".
