27 FEB 44
February 27th was almost a day of rest for the men of The Peerless P, which seems fitting since it was a Sunday.
Only three aircraft left her deck, the first two being "1 VT and 1 VF for special flight to land at field on Engebi Island with Air Combat Intelligence Officers."
After US forces had landed on Engebi its airfield was hastily repaired by the U.S. Army's 47th Engineers and renamed "Wrigley Airfield." The extent of the repairs, or perhaps the landing technique of the pilot, was put in question by the fact the War Diary notes the launch an hour and a quarter later of "1 VT for special flight to Engebi Island field to deliver spare landing wheel for VT from this ship which had reported damaging wheel in landing there."
With yesterday's discussion regarding the impressive buildup of the Navy in mind, consider what else American muscle and the American economic system was accomplishing:
"Wrigley Airfield, on Engebi Island, was built to support four squadrons of Marine fighters until sufficient space at Eniwetok became available for their operation. The 126th Battalion arrived at Engebi on March 11, 1944, and took over development of this airfield from the 47th Army Engineers. Aviation facilities, when completed, included a fighter strip, 3950 by 225 feet, taxiways with 150 hardstands, and engine-overhaul shops. A tank farm of twelve 1,000-barrel tanks, with piping, a floating pipe-line, 1,200 feet long, and a tanker mooring, was completed for aviation gasoline on Eniwetok Island by May 1944. Completion had been delayed by the explosion of an LCT in March, which reduced the status of completion of the farm from 80 to 30 percent. An aviation-gasoline tank farm, with a capacity of 146,000 gallons and all appurtenances, was also erected on Engebi. Two coral-fill piers, one 80 and the other 150 feet long, were built on Eniwetok Island, and two beaches were developed for LCT's. Small-boat-repair shops were also built, and a floating dock for small ships was assigned to the base. At Parry Island, a marine railway was installed on an existing Japanese pier, and boat-repair shops were also erected. The Seabees repaired a 30-by-150-foot Japanese pier at Engebi, with timber piling, to accomodate small craft, including LCM's. Medical facilities were provided by three dispensaries with a total capacity of 200 beds, one each at Eniwetok, Engebi, and Parry islands. Quonset huts and tents were erected for base storage and housing. By June 1944, the major work projects on Engebi had been completed and CBMU 594 reported to take charge of maintenance activities. The 126th Battalion, pending its departure in October, was assigned to small projects on several islands in the atoll, including construction of a fleet recreation center on Hawthorne Island. CBMU 608 arrived in August 1944 to relieve the 110th Battalion, which left in September. The air base on Engebi was decommissioned on September 18, 1944."
Impressive.
Two Marine F-4U Corsairs at Wrigley Airfield, Engebi Island, 1944
Shifting gears...
I have had a couple of inquiries regarding Princeton's 1 year anniversary statistics, specifically the seemingly low number of catapult shots (897) when compared to the much larger number of landings (3,828). Keeping in mind that I are a pilot and not a "thirty pound head" test pilot astro-nerd, I will endeavor to explain.
Generally speaking, aircraft engines perform better in cold air versus hot air. This is particularly true for jet engines but it applies to propellor-driven aircraft as well (all naval aircraft in the Pacific theater at the time were props). Thrust can be explained using the simple formula...
F = (m dot * V)e – (m dot * V)0 + (pe – p0) * Ae.
Obviously.
In the non-sciency world I inhabit,
the engine produces power...
which spins the propellor...
which "bites" into the air...
which creates the force...
which is translated into thrust...
which propels the aircraft forward.
Duh.
For now, let's discuss the air. Specifically, the more air molecules into which the propellor can bite, nerds refer to this as the "mass flow rate," the more forward force can be created.
Because...science!...we know that in cold temperatures the air molecules are slower and more compressed than they are in hot, humid air:
(Don't even mention air density as it relates to altitude or the adiabatic lapse rate lest we run out of pixels...but if you're interested, air temperature decreases by approximately 2˚F for every 1,000 feet of altitude increase. For today's discussion, considering we are limiting the conversation to launching from sea level, we don't care about the lapse rate)
Ergo, in cold air a propellor has more air molecules at which to bite so it stands to reason that more forward propulsion can be achieved in cold versus hot air. (For this same reason, all things being equal, a golf ball that I hit on a hot, humid summer day will travel farther than the same shot I hit in the shrinkage-inducing cold of winter because it will have fewer air molecules to "run into" as it arcs its way 20 yards out into the rough)
So what does this have to do with Princeton's lopsided cat shot and landing numbers!?
During WWII, the vast majority of aircraft carrier launches were what were called "deck launches" or "deck runs," which were simply as described: turn the ship into the wind, run up the aircraft's engine, release the brakes, maybe pray a little, and by the end of the deck you should be flying. OK, that is an oversimplification of sorts, but not entirely inaccurate.
The large-gonaded Eugene Ely made the first ever deck launch of an aircraft from a ship on January 18th, 1911. And yes, that is a football helmet on his head and a bicycle inner tube life preserver.
However, recall from and earlier post that Lieutenant Commander Henry Miller, Air Group 23's CAG, helped train then-Colonel Jimmie Doolittle's bomber crews to take off from an aircraft carrier. Eugene Ely's significant accomplishment aside, to see perhaps the most famous deck launch in the history of Naval Aviation, ironically accomplished by Army pilots, go to the 1:50 mark of this video:
Another factor that helped accomplish a deck launch was natural wind. The carrier always prefers to be pointed into the wind, which helps create the lift an aircraft needs to fly. An added bonus is that natural wind is free. If there is 25 knots of natural wind and an aircraft needs 28 knots to accomplish it's takeoff roll before it runs out of deck, the ship would need to create the additional 3 knots with it's own engine and it's underwater propellor.
One of the four propellors of USS Gerald Ford (CVN-78).
The boats I cruised in, "Connie" and "Indy", were both powered conventionally, that is to say, they were not nuclear powered. I recall that Connie produced a pamphlet for visitors and one of the eye-popping statistics listed regarded her gas mileage as an impressive 12 ipg.
Yes, every 12 inches of travel required 1 gallon of fuel oil.
The moral of this story? Natural wind is good because it helps you fly and because it is free.
Ok, ok, ok...so thus far we have discussed the importance of air temperature and wind. The next most important factor is — recall our thrust-drag-lift-gravity discussion of several weeks ago — the weight of the object with which you are trying to defy gravity. In this case, obviously, the weight of the aircraft.
The more the aircraft weighs, the more power it needs to fly.
Right now you all are saying (if you've read this far) "OMG! Make him stop putting this red-hot poker in my eye!" Don't worry, it will all be over soon.
While the War Diary doesn't specify, I think it is reasonable to assume that catapult shots from Princeton were likely only conducted during:
- hot days
- when launching a heavy aircraft, likely an Avenger, perhaps carrying a 2,000 pound bomb
- during times of little or no natural wind
Which, if my math is correct, was about 23% of the time.
I am now ready for some medicinal Brandy. Good day!
NNNN
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