Ever the historian, ComNavOps likes to re-examine ships, tactics, and campaigns to glean lessons learned. In that vein, let’s take a look at the remarkable Pegasus class hydrofoils (PHM, Patrol, Hydrofoil, Missile). These vessels are often cited as possible alternatives or adjuncts to the more conventional fleet assets. Here’s a quick reminder of their characteristics.
PHM (Patrol, Hydrofoil, Missile)
Cost: $870,000 each (1)
Service: 1977 – 1993
Length: 132 ft
Displacement: 240 tons
Speed, hullborne: 12 kts
Speed, foilborne: 48 kts
Sensor: Mk92 Mod 1 Fire Control
Armament: 8x Harpoon, 76 mm Oto Melara gun
Propulsion: 1 GE gas turbine (foil) and 2 diesel (hull) with water jets
Range: 750 nm – 1200 nm, depending on propulsion mix
Draft: 7.5 ft (foils raised), 23 ft (foils lowered)
For their size, the vessels had good range and excellent seakeeping with an ability to maintain high speed in high sea states.
The PHM was a bit of a pet project of then CNO Zumwalt. The PHM was to be part of the hi-lo mix concept being championed by Zumwalt. Costs were an issue, apparently, although the degree of unconventionality may have largely contributed to the price tag. Regardless, upon Zumwalt’s retirement, funding was redirected towards more conventional ships and the project languished until Congress intervened and forced completion of six of the vessels.
The PHM program was originally envisioned as a NATO response to the numerous Warsaw Pact missile boats and included plans for around 30 ships and participation by Germany and Italy. In the end, only six vessels were built and none for any foreign buyers.
The PHMs were envisioned to be minimally manned and include a mothership for maintenance and support. Manning and crew activities were to be limited to port/starboard watches. Maintenance, logistics, and support were to be provided by a converted LST acting as the mothership. We see, then, that the ships were designed to the same operational manning and maintenance concept as the LCS.
It was originally intended to operate the PHMs in the Mediterranean, Baltic, and North Seas with a homeport in Sicily. In actuality, the PHMs wound up operating exclusively in the Caribbean, largely involved in the war on drug efforts where they were quite successful due to their high speed and maneuverability.
The class was eventually terminated and retired though no reasons were ever offered beyond vague cost issues that were not valid. The real reason was, undoubtedly, that lacking the sponsorship of the CNO, the “big” Navy simply had no use for small vessels and no desire to attempt to integrate them tactically or operationally into Navy missions.
|Pegasus Class Hydrofoil|
The PHM packed a large punch for its size and represents the Hughes approach to distributed lethality. The weakness in this approach is the lack of over the horizon sensing. The weapon, the Harpoon anti-ship missile, outranges the sensor. Such a vessel would either be dependent on off-board sensors or need to get much closer to the target, thus negating much of the standoff range of the weapon and increasing the risk to the launching vessel. In littoral warfare where coastlines might offer concealment and ambush possibilities, the lack of sensor range might be acceptable. The PHM offers a real world experiment in the Hughes distributed firepower concept. Unfortunately, the vessels never had the opportunity to operate in their intended environment and this limits the ability to draw conclusions about their potential combat effectiveness.
The PHM was a remarkable vessel and the similarities and parallels between it and the LCS are interesting. The PHM was intended to use the exact same manning and maintenance model that the LCS is now attempting to use. The firepower (76mm and 8x Harpoon) of the PHM is, arguably, greater than the LCS and certainly far greater in terms of weapon density. Further, the indifference of “big Navy” to both their uses is striking.
It is worth noting that the Chinese (and other countries) are developing the Type 022 Houbei class missile boat which is a functional equivalent of the Pegasus PHM. Would squadrons of PHMs offer a viable counter to Chinese missile boats? It’s something to think about.
Here’s a nice summary of the class.