James N. Gibson

A disappointing book.

The various back-cover and inline blurbs for this make no bones about it: Navaho was an early missile, the most important missile on which all major innovations were founded, and a largely unknown missile. It then goes on to illustrate two of these three.

Navaho was an unusual missile, being a ramjet-powered winged upper stage on a rocket-launched booster. At the early time this project began, that was so adventurous that a 2-step, later 3-step, development plan was put forward where effectively three different misiles would be constructed. Starting from a base of almost no knowledge. It was indeed a heroically brave project. Simultaneous to it were the subsonic Snark winged missile and the pure rocket Atlas, all intended to give the USA its first intercontinental nuclear missile. In hindsight, the rocket developments overtook both winged projects, and now the Snark and especially the Navaho are barely known.

The most successful part of the project was probably the first step, the X-10; a winged pilotless aircraft powered by existing turbojet engines, yet capable of taking off from a runway, accelerating to Mach 2, guiding itself autonomously along a long flight plan and then landing back on its own runway. Some remarkable achievements indeed, both for being the fastest turbojet aircraft of its time and also for the development of the N-6 NAVAN inertial navigation system.

The second step was also tested, the G-26 combination of a rocket booster and a new winged stage with huge ramjets for propulsion. This was also flown successfully (sometimes) from Cape Canaveral in Florida. The Atlas overtook though and the delayed Navaho project was cancelled before the final G-38 versions could be flown.

This is not a thick book. It is based on personal experience and interviews from those involved with the project, rather than searching of the technical archive (still substantially classified, at time of writing). It is also padded a lot by non-Navaho material: precursors from the V-1 and V-2, through to claims that every supersonic aircraft with canards was somehow based on the Navaho work. Or that the whole Rocketdyne S-3D rocket engine family was little more than a reworked Navaho booster engine. This use of space, and these claims, would carry more weight if the book had more technical depth. But it's shallow. Very shallow. If you come here expecting a history of the invention of inertial navigation (that is after all what the back-cover claims for Navaho), then you'll be sorely disappointed. Likewise the claims for the rocket engines, which are barely mentioned, and not in any technical detail.

It may be that this was the best and only book on Navaho around at the time. Perhaps it still is. But Navaho's unquestioned technical innovations deserve a lot better.… (plus d'informations)