Pre-Vietnam: Development of the PTF Nasty
History for the PTF began in the late 1950's when the prototype motor
torpedo boat NASTY was developed for the coastal anti-invasion mission of
the Royal Norwegian Navy, as a follow on to their U.S. built PTs and
British Fairmile "Ds". It was a private venture financed by
shipyard entrepreneur Westermoen.
The NASTY was designed by Jan H. Linge in close cooperation with World
War II experienced officers of the Royal Norwegian Navy. Linge used a
computer to analyze the features of the best patrol boats developed up to
that time and to test improved designs. The prototype was completed in
Autumn of 1957 and it was successful in tests by the Royal Norwegian Navy.
the Spring of 1958 an order was placed for 12. Lead boat KNM TJELD (P-343)
was commissioned in June of 1960 (tjeld is a type of seabird). This class
was designed to fit guns, torpedoes, mines and/or ASW weapons. These craft
have proven to be very fast, with a burst speed of 46 knots fully laden in
calm water. Top speed varies slightly from boat to boat due to small
differences in the construction of their wood hulls. Initial cost was
relatively low, as is the cost of operation and maintenance.
Survivability features include low silhouette and low radiated
signatures (magnetic/IR/acoustic). There is redundancy in the engineering
plant, with manual backups for pumps and steering. Watertight
compartmentalization includes features of fire and flooding control, as
well as protection from nuclear, biological, and chemical contamination.
The extremely wide beam (about 1/3 of the length) incorporates a
"V" bottom, hard chine after part with a round bottom forward.
It efficiently carries heavy loads and a large crew of 19 plus two
squadron staff members. Due to her long range capability of over 1000
miles, seats are provided for the steersman and commander. During cold
weather operation, heated suits are worn by those in the open bridge.
The NASTYS feature British Napier (now Paxman) Deltic turbo-charged
opposed piston diesel engines (18 cylinders). They have integral gear
boxes which connect to "V" drives, with a ratio of 1:1, and
develop 3100 S.H.P. each. These fresh water cooled engines are made mostly
of aluminum, have low magnetic signatures, run cool to the touch and weigh
only 13,000 pounds. They were developed based on fast patrol boat
experiences of World War II. First fit in the Royal Navy DARK class in
1953, these engines have since served in 18 navies, and have operated from
the arctic to the tropics. Most engine exhaust is directed underneath the
hull to muffle noise, minimize infrared (IR) signature, and reduce water
resistance. Royal Norwegian Naval experience with the engines has been
excellent, with overhauls scheduled after normal operations of 1,500 hours
a year. The engines can be lifted out and replaced easily to minimize boat
Selected for Vietnam
In all, 42 NASTYS were built in Norway: 20 for their own Navy's use,
six for Greece, two for Turkey (as war reparations from West Germany), and
14 were built for the US. Designated PTF, these 14 were bought for use in
Vietnam. Six more PTF's were built in the U.S. by John Trumpy and Sons of
Annapolis, Maryland (some parts, such as the keel and stem were imported).
In Vietnam they operated out of DaNang, were crewed by the South
Vietnamese Navy, and carried 12 man Vietnamese Army SEAL Teams. The NASTY
PTFs supplemented a large U.S. force of aluminum hulled patrol boats.
[Portions of "Pre-Vietnam" and "Selected for
Vietnam" contain excerpts from "FAST FIGHTING BOATS", A
NASTY PERSPECTIVE, By John Stebbins to the American Society of Naval
Engineers, March 13, 1986 "PATROL BOATS 86," A Technical
The US Navy trained Vietnamese crews on Norwegian Boats. These boats
were active in coastal bombardment, covert maritime operations, and
amphibious raids against transshipment points to destroy/disrupt normal
logistic flow. They were used to intercept and destroy infiltration
trawlers that had been designated a threat and destroy/disrupt the North
Vietnamese fishing industry along the coast of North Vietnam.
of History Section Pages
NEW - PTF Nasty's
designer passes away.
Coastal Raiders -
an English translated version by
Tran Do Cam, Ex-skipper of PTF 2 & 11, DaNang, Vietnam
- The History
of PTFs in Coastal River Division - Twenty One -
written by Robert Stoner, USNR - (01-05-07
Current History of CRD-21 and all other Units here)
Review about PTF related subjects
- From his personal experiences, Jim Gray has written a
very in-depth article covering the Vietnam years and
beyond. I have titled it Vietnam
- Take a trip up North with the crew of PTF
Zero Six in this 3-part history written by Thong Ba
Le a Vietnamese boat commander that was there.
- Pictorial collection from of DaNang
Harbor with charts and photos from readers
Communism Credentialism, full text of August '99
Vietnam feature article from the History Channel.
- Operation Vulcan,
U.S. Naval Institute - Naval History - The Secret Side
of the Tonkin Gulf Incident by Dale Andrade and Kenneth
- New Contend from
Gulf of Tonkin Resolution
New source found - The
Side of the Tonkin Gulf Incident by By Dale Andradé
and Kenneth Conboy - Web Edition
- Stalking The Enemy's Coast,
a magazine article from Proceedings / February 1992.
- R. Angus Murdoch submits his research notes on: The
History of the PTF "Nasty" Boats in Viet Nam.
- MACV/SOG, a highly
classified project only now becoming de-classified
describing the activities of the Military Assistance
Command, Vietnam, Studies and Observations Group
- Historical Advertisements
for PTF Nasty and Deltic Engines
- UDT Museum, located in southern