Sikorsky S-61

Infobox Aircraft
name=S-61L/S-61N


caption= HeliJet's S-61N at Vancouver International Airport
type=Medium-lift transport/airliner helicopter
manufacturer= Sikorsky Aircraft
designer=
first flight= March 11 1959
introduction= September 1961
retired=
status=Active service
primary user= Canadian Coast Guard
more users= CHC Helicopter Bristow Helicopters HeliJet
produced=
number built=119
unit cost=
developed from = SH-3 Sea King
variants with their own articles= Sikorsky S-61R

The Sikorsky S-61L and S-61N are civil variants of the successful SH-3 Sea King helicopter. They are two of the most widely used airliner and oil rig support helicopters built.Frawley, Gerard: "The International Directiory of Civil Aircraft, 2003-2004", page 194. Aerospace Publications Pty Ltd, 2003. ISBN 1-875671-58-7]

Design and development

In September 1957, Sikorsky won a US Navy development contract for an amphibious anti-submarine warfare (ASW) helicopter capable of detecting and attacking submarines. The XHSS-2 Sea King prototype flew on March 11 1959. Production deliveries of the HSS-2 (later designated SH-3A) began in September 1961, with the initial production aircraft being powered by two 930kW (1250shp) General Electric T58-GE-8B turboshafts.

Sikorsky was quick to develop a commercial model of the Sea King. The S-61L first flew on November 2 1961, and was 4ft 3in (1.27m) longer than the HSS-2 in order to carry a substantial payload of freight or passengers. Initial production S-61Ls were powered by two 1350shp (1005kW) GE CT58-140 turboshafts, the civil version of the T58. The S-61L features a modified landing gear without float stabilisers. Los Angeles Airways was the first civil operator of the S-61 [ [http://www.aviastar.org/helicopters_eng/sik_s-61n.php Sikorsky S-61N] ] introducing them on March 1, 1962 for a purchased price of $650,000 each. [ [http://www.time.com/time/magazine/article/0,9171,895186,00.html "The Self-Supporting Helicopter"] Time Magazine December 26, 1960]

On August 7 1962, the S-61N made its first flight. Otherwise identical to the S-61L, this version is optimized for overwater operations, particularly oil rig support, by retaining the SH-3's floats. Both the S-61L and S-61N were subsequently updated to Mk II standard with improvements including more powerful CT58-110 engines giving better hot and high performance, vibration damping and other detail refinements.

The Payloader, a stripped down version optimised for aerial crane work, was the third civil model of the S-61. The Payloader features the fixed undercarriage of the S-61L, but with an empty weight almost 2000lb (900kg) less than the standard S-61N.

A unique version is the S-61 Shortsky conversion of S-61Ls and Ns by Helipro International. The fuselage is shortened by 50in (1.6m) to increase single engine performance and external payload. The Shortsky conversion first flew in February 1996.

Variants

;S-61L : Non-amphibious civil transport version. It can seat up to 30 passengers (13 Built).;S-61L Mk II : Improved version of the S-61L helicopter, equipped with cargo bins.;S-61N : Amphibious civil transport version.;S-61N Mk II : Improved version of the S-61N helicopter.;S-61 Payloader : Stripped down machine optimised for aerial crane work; features the fixed undercarriage of the S-61L, but with an empty weight almost 900kg (2000lb) less than the standard S-61N.;S-61 Shortsky : Shortened conversion of the S-61L and N, designed to increase single engine performance and external payload.

Operators

:"Former operators are marked by italics";GRL
*Air Greenland;CAN
* CHC Helicopter
* Canadian Coast Guard
* HeliJet
* Cougar Helicopters
* VIH Helicopters;GBR
* BEA Helicopters
* Bristow Helicopters
* British Airways Helicopters
* British Caledonian Helicopters
* British International Helicopters;NLD
* KLM Helicopters;PAK
* Pakistan International Airlines;USA
* Carson Helicopters
* "Columbia Helicopters"
* Croman Corporation
* "Los Angeles Airways"
* "New York Airways"
* San Bernardino County, California Sherriff's Department;IRL
* Irish Coast Guard (CHC Helicopter)

Notable accidents

* On May 22, 1968 Los Angeles Airways Flight 841 crashed near Paramount, California, resulting in the loss of 23 lives. The accident aircraft, Airreg|N|303Y|disaster, serial number 61060, was a Sikorsky 61L en route to Los Angeles International Airport from the Disneyland Heliport in Anaheim, California.
* On August 14, 1968 Los Angeles Airways Flight 417 crashed in Compton, California, while en route to the Disneyland Heliport in Anaheim, California from Los Angeles International Airport, resulting in the loss of 21 lives. The accident aircraft, Airreg|N|300Y|disaster, serial number 61031, was the prototype of the Sikorsky S-61L. [http://www.airdisaster.com/reports/ntsb/AAR69-07.pdf Aircraft Accident Report. Los Angeles Airways, Inc. S-61L Helicopter, N300Y, Compton, California] , Adopted: August 27 1969]
* On July 16, 1983, British Airways Helicopters' commercial S-61 G-BEON crashed in the southern Celtic Sea, in the Atlantic Ocean, while en route from Penzance to St Mary's, Isles of Scilly in thick fog. Only six of the 26 on board survived. It sparked a review of helicopter safety and was the worst civilian helicopter disaster in the UK until 1986.
* On August 5, 2008,two pilots and seven firefighters assigned to the Iron Complex fire in California's Shasta-Trinity National Forest, perished in a crash as they were taking off from a helispot in a Carson Helicopters Sikorsky S-61N helicopter (N612AZ). Of the 13 people reported to be on-board, one other pilot and three firefighters survived the crash. The four survivors were subsequently transported to hospitals with serious and some critical injuries. The cause of the incident is under investigation. [cite news
title = USFA Fatality Notice
url = http://www.usfa.dhs.gov/applications/ffmem/ffmem_results.jsp?p_mn_status=1&p_last_name=&p_first_name=&p_fd_city=&p_fd_state_code=&p_death_year=2008
publisher = United States Fire Administration
date = 2008-08-05
accessdate = 2008-08-11]

pecifications (S-61N Mk II)

Aircraft specifications
plane or copter?=copter
jet or prop?=prop

ref=International Directiory of Civil Aircraft

crew = 2 pilots
capacity = up to 30 passengers
length main=58 ft 11 in
length alt=17.96 m
height main=17 ft 6 in
height alt=5.32 m
span main=62 ft
span alt=18.9 m
area main= 3,019 ft²
area alt= 280.6 m²
empty weight main=12,336 lb
empty weight alt=5,595 kg
loaded weight main= lb
loaded weight alt= kg
max takeoff weight main=19,000 lb
max takeoff weight alt=8,620 kg

engine (prop)=General Electric CT58-140
type of prop=turboshafts
number of props=2
power main= 1,500 shp
power alt= 1,120 kW
max speed main=166 mph
max speed alt=267 km/h
cruise speed main= 120 kn
cruise speed alt= 222 km/h
never exceed speed main=
never exceed speed alt=
range main= 450 NM
range alt= 833 km
ceiling main= 12,500 ft
ceiling alt= m
climb rate main=1,310-2,220 ft/min
climb rate alt=400-670 m/min
loading main=
loading alt=
thrust/weight=
power/mass main=
power/mass alt=
more performance=

armament=

ee also

Aircontent
related=
* SH-3 Sea King
* HH-3F Pelican
* CH-124 Sea King
* Westland Sea King

similar=

lists=

see also=

References

External links

* [http://avia.russian.ee/helicopters_eng/sik_s-61n.php Sikorsky S-61N on avia.russian.ee]
* [http://www.ccg-gcc.gc.ca/helicopter/carct_sik_s61-n_e.htm Canadian Coast Guard S-61N Characteristics page]
* [http://www.flightglobal.com/articles/1996/04/03/17432/helipro-shortsky-enters-service.html "Helipro Shortsky enters service" FlightGlobal]
* [http://www.flugzeuginfo.net/acdata_php/acdata_s61n_en.php S-61N Specs & Photo on flugzeuginfo.net]