It seems to me that the early A36/P51's were Allison powered and were lacking in high altitude performance, disappointing the Army Air Corps. When the British bought them, they installed the Merlin engines that made the plane a force to be reckoned with. The Packard version was a Merlin built under license.
For those less skilled at detailed handiwork, there was a company called 21st Century Models and were part of the Ultimate Soldier line of pre-built military models. In particular, were the large 1/18 scale, WWII fighter airplane models. Every major Allied plane and most of the well known Axis ones were available. Originally costing over $75 each, these were all wonderfully painted and detailed that an amateur modeler would have a hard time competing with. They were also issued in different liveries and pilots. They included pilots, ground crew, bombs and rockets, drop tanks, and more. All you had to do was take them out of the box and plug in the wings. The landing gear could be up or down and canopies and cowls could be moved. Out of business since 2008, the secondary market is based on desirability and rarity. I believe they also got into military jets, but I never was interested. I have 6, including a P-38, Corsair, P-51, Spitfire, Stuka, and ME-109. Sadly, I have to pass them on, now.
Tony is absolutely right. The early P51 sent to the european theatre with the Allison V12 was a dog. When retrofitted with the Rolls Merlin it became the outstanding legend we all know. The Packard used was a Rolls Merlin built under license by Packard and it only made sense to install the American made version into the American built Mustang as well as the Canadian built Hurricane, Mosquito and Lancaster
I had a Blue Devil destroyer that I and (mostly) my dad built, which I used in the family pool. Had battery powered propellers and a cam wheel system that allowed it to cruise through different manuevers. After running it so much that the petroleum jelly shaft packing gave up, it ended at the bottom.
Tony T is correct; the early P-51 had an Allison V12-1710 cubic inch engine that was similar to the type used in the P-38 Lightning, P-39 Aircobra, the P-40 Warhawk, P-63 King Cobra and P-82 Twin Mustang. Except for the P-38 Lightning, which was also turbo-charged, the other aircraft used single-stage, single speed centrifugal superchargers, England's Rolls Royce Merlin was a 1650 cubic inch V-12 with a s-stage, 2-speed supercharger, better suited to chasing high altitude, German Fighters. Through the lend-lease program, England acquired sever P-51s and found that the Aiison just couldn't make the grade, so they inserted some Merlins into the Mustang and found out that the "improved" Mustang was a "rocket"! It could outperform ANY other fighter at low and high altitude. Packard received a license to build Packard Merlins for the U.S. built Mustangs and the rest is history. By the way, the American PT boats did not use the Merlin, but rather used three Allison V-12s in each boat. They were extremely fast on the water...
Allison powered Mustangs were superior to Merlin powered ones at low altitude; that just wasn't what was needed in Western Europe. American PT boats used Packard engines which were quite a bit larger than the Allison & Roll Royce aircraft engines.
The Humvee was a terrific weapon for what it was designed for, fighting a land war in Europe. Not so good in the desert. Same story with the Blackhawk helicopter and the Abrams tank (remember those?). From the end of WWII until the last decade we designed vehicles to fight on the large open plain that runs from East of Berlin to Moscow, and then had to play catch up when we ended up fighting in the jungle or desert or mountains. The latest Army reorganization creates what is basically a highly flexible set of quick reaction groups, betting heavily on the Stryker light armored vehicle. Terrific for fighting insurgents, not so good for that land war in Europe or China. That's why it's inevitable that the next big war will be a nuclear war - at this point we simply lack the ability to fight a world power on the battlefield.
I think a general kudos should go in Revell’s direction; they were the go-to best combo of quality/detail and affordability when I was a model building kid 50 years ago and they’re still at it. Built the spitfire as my first WWII airplane and never looked back.
BF 109 Messerschmitt Cannon? This plane had a 30mm cannon barrel in the propeller nose cone. Not sure but I believe this Luftwaffe combat plane had 6 rounds at it's disposal. Picture a round the approximate size of a 30mm impact deep socket being fired at your belly.