Not near this short, but quite a few years ago a Hawaii Airlines flight had an in-air fuselage failure in which a large chunk of the top of the fuselage came off. The plane managed to land with the only fatality being a flight attendant whose body was never found. It was determined that due to the short duration of most of their flights, (distances between islands are relatively small) the large number of landing and takeoff cycles proportionate to total flying time resulted in accelerated body metal fatigue, which is normally taken as being a function of hours in the air.
(EDIT) See West Point's corrections below. My statements were from what appears to be a rather incomplete memory. At one point I read the NTSB report, and high takeoff/landing frequency relative to total flight hours was mentioned. Recall seeing a picture. "Great big convertible" was exactly what it looked like. That the pilot was able to bring this thing into a landing was somewhere between astounding and miraculous. Consider what this change did to the aerodynamics of the plane, plus what was the damage to the tail when it was impacted, as it most certainly would have been by the fuselage pieces? It is amazing this did not simply crash.
George. Believe some corrections are in order.
1. The aircraft was a B-737-200 that UAL ordered that were in a consecutive group of 6(?).
2. Boeing used an experimental method of connecting the skin of aircraft to stringers in the group.
3. UAL retired the airplanes, and they were sold to different airlines.
4. The attaching method did not work and the skin just pealed back making a great big convertible.
5. There was a lost flight before the Hawiian incident on some other airline ( turned up missing ) that no cause was determined.
6. All aircraft in that serial number series were quickly retired. Even before final determination of Hawiian incident cause.
For decades I have thought that these island hoppers should be replaced with ferries, as the island-hopper planes are horribly inefficient and polluting. But most of the people prefer the island-hopper airplanes because of speed.
So now there's a new alternative coming along: small electric airplanes. They work very well for these tiny island-hopper routes. I look forward to them displacing the high-pollution fuel-burning planes. First airline to use them widely will probably be Harbour Air in Vancouver, BC, Canada; but I hope other routes like this one take note and follow suit.
IMO a ferry boat is going to burn much more fuel. A 1500 pond airplane compared to a 20 - 40 ton ferry boat pushing thru water? water is much more resistant than air. Do all these islands have a slip for occasional ferry supply trips?
Again, West Point, thank you for your corrections on the Hawaii Air instant convertible flight.
The fuel usage by both means can be calculated, but I am not going to try to find the numbers for these alternatives right now. However, I am inclined to suspect that the fuel usage for the ferry would be less, and probably much less. Given the short distance, don't see how time could be that much of a factor, either. As an approximation from someone I know in a business that moves petroleum products in bulk, their statement on general relative costs in a completely unrelated context was that movement on water was about 1/4 the cost of movement by rail, which would itself be less expensive than by road.
Most of your fuel in the air mode would be expended in takeoff acceleration and climbing, with the engines little more than idling on descent and landing. There would be no real cruise at a level at any altitude on this short of a flight. For the ferry, assuming a speed in the order of 10 knots or thereabouts, and it would likely be less, your acceleration effort would be very small. Outside channels, water has an essentially unlimited movement potential which significantly reduces resistance to movement.