Most aircraft don’t fly too well without engines, and advances in propulsion technology have literally propelled aviation to its heights. Several engines offer themselves as the most significant of the last 100 years: the Rolls-Royce Merlin that helped the Allies win the Second World War; the Pratt & Whitney JT8D that at one time powered most of the western world’s jetliners; the General Electric/Snecma CFM56 that seems to power most of today’s jetliners; the P&W J58 that enabled Lockheed’s SR-71 Blackbird to cruise at more than three times the speed of sound; the R-R Pegasus that enabled Hawker’s Harrier to take-off and land vertically; and the GE90-115B with its world-record 127,000lb of thrust.
 

 
Pinned to the wall and asked to pick just one engine for its significance, I have selected the Rolls-Royce RB.41 Nene – an engine that I feel did more than any other to bring aviation around the world into the jet age. The Whittle-style Nene was R-R’s third production jet engine, developed over five months and first run in 1944. The Nene powered the Hawker Seahawk and Supermarine Attacker and, built in the US by Pratt & Whitney as the J42, the Grumman Panther and Cougar.

 
But the Nene also gave several countries their first post-war taste of turbine power, propelling France’s first jet, the SNCASO SO.6000 Triton, as well as the first of a long and successful line of Dassault jet fighters, the MD.450 Ouragan. Others to exploit the Nene were Argentina with the Kurt Tank-designed FMA IAe.33 Pulqui II, and Canada with the Canadair CT-33. The Nene also powered some early attempts at jet airliners, including the Avro Ashton, SNCASO SO.30 and Vickers Nene Viking.

 But the engine’s greatest claim to fame – or notoriety – resulted from the British government’s post-war decision to sell 25 Nenes to the Soviet Union as a goodwill gesture. The Nene was promptly reverse-engineered to produce Russia’s first jet engine, the Klimov VK-1. This was a leg-up (or ***-up) of historic significance, as the engine went on to power thousands of Mikoyan MiG-15 fighters and Ilyushin Il-28 bombers.

The GE J-79 : another milestone in propulsion technology .....

Near 17,000 were built worldwide for thousands of Mach 2 aircraft: F-4 Phantom, F-104 Starfighter, A-5 Vigilante, B-58 Hustler and IAI Kfir.

Mr. Bill Gunston, renowned (and prolific) british aviation writer, as well as former Flight International Technical Editor, wrote :

"Fortunately, GE had also created a superb successor to the J47 to fill the expanding new plant at Evendale outside Cincinnati, Ohio. 

In March 1952 it was decided to go ahead with a totally new turbojet offering fuel economy at Mach 0.9 and high thrust for Mach 2.

The key was increased pressure ratio, and the choice was between a two-shaft 'split compressor' design, as adopted by P&W and Bristol, or the completely new single spool with variable stators, which was already in preliminary test by GE's Gerhard Neumann.

After intense research and argument (who knows how far the decision was influenced by a wish not to copy the competition?), the choice fell in November 1952 on the variable stator.

The result, via the GOL-1590 demonstrator, was to become famous as the J79, first run on 8 June 1954, flown under a B-45 in 1955, and tested in an XF4D Skyray from 8 December 1955.

Probably the world's first fully engineered Mach-2 propulsion system was seen in the XB-58  bomber, first flown in  November 1956 .

Altogether just under 17,000 J79 were built, 3,249 by licensees.

They set 46 world records, and until Concorde had more Mach 2 time than all other engines combined (said GE)."

From :  "The Development of Jet and Turbine Aero Engines" - Patrick Stephens Limited - 1995

GE J-79