Stony Isle, launched in spring 2016, is our first fully Coast Guard-approved commercial commuter yacht and the second vessel in our semi-custom Monhegan 42 line. Our customer, who was looking for an executive lauch that could ferry 15 people at a time to an island retreat on Lake Ontario, came to Lyman-Morse after reading the rave reviews of Peregrine, Monhegan 42 hull No. 1. They did their due diligence on us, which revealed that we have built 17 legendary C. Raymond Hunt hulls over the years. This was an important track record for this client, since they knew that Hunt’s legendary deep “V” design would ensure great performance, handling passenger weight and rough weather with ease. Even better, the Monhegan 42’s hull shape fit their draft and beam restrictions. After a site visit to Thomaston and a test run on Peregrine, they were as blown away by the performance of this design and our crew’s attention to details as they were by our boatbuilding facility.

USCG certification is even more stringent than ABS (American Bureau of Shipping), our usual design standard for new yachts. For boatbuilders, building Coast Guard-approved boats is always a challenge, since so much of the process largely depends on the individual inspector and how they read the various regulations – some which are often outdated by new materials and systems. Until an update is made, the inspectors have their hands tied and builders can be left in a lurch.

To ensure compliance with the federal standards, Steve Crane and our composites team sent sample panels representing different hull laminates to be lab tested. They compared tensile and compression strength and modulus, sheer strength perpendicular and parallel to warp, interlaminar shear strength, glass content and ply-by-ply analysis, core-to-skin bond line and shear strength composite. Fireproofing and fire retardation was a focus throughout the yacht as well. The hull topsides, hull bottom inner and outer skins, and sandwich core were all infused with Hetron FR992, a low-viscosity, flame-retardant patented epoxy vinylester resin. Electrical, mechanical and safety systems were scrutinized for compliance with the USCG requirements for “Subchapter T” small passenger vessels, leading to a few changes from our first Monhegan 42: watertight bulkheads, larger cockpit scuppers, taller bow rail, and wider passage entry and doors.

This executive launch is nonetheless a Lyman-Morse boat and so the interior accommodations are both functional and beautiful. The comfortable upholstered settee seating with custom armrests on either side of the pilothouse gives a casual feel for the 11 passengers seated inside and facilitates conversation during the commute.  Those who prefer a little fresh air can sit in open seating in the C-shaped transom seat or find a little more shelter in the seating along the aft bulkhead.   Passengers are kept comfortable with air conditioning and reverse-cycle heating for the late fall runs on the lake, all within an elegantly finished interior of varnished mahogany.


  • loa 42'
  • lwl 35'6"
  • beam 13'
  • draft 3'
  • displacement
  • fuel capacity 450 gals
  • type Power
  • designed by C. Raymond Hunt & Associates/Peter Boyce
  • builder Lyman-Morse Boatbuilding Co.
  • model Monhegan 42 commuter
  • year 2016
  • construction SCRIMP infused with Hetron FR 992 fire-retardant vinylester
  • hull material Fiberglass
  • configuration Commuter Yacht
  • boat engine Twin Cummins diesel B 6.7, plus Sidepower stern and bow thrusters
  • horsepower 480 hsp
  • cruising speed 28 knots
  • top speed 32 knots