Delta Green - страница 3

Forty thousand feet was the prime altitude for starting the jet engines. The MakoShark operated on both rocket motors and turbojets, depending on the need at the time. Additionally, for high altitude missions, there was a ramjet mode.

McKenna retracted the ramjet cones — triangles, actually — in the turbojet intakes, and Munoz intoned the start checklist, which also scrolled down the smaller, four-inch CRT on McKenna’s instrument panel.

The HUD showed the RPMs coming up on both engines, and at 25 % RPMs, he activated the ignition and fuel flow. A few seconds later, the tailpipe temperature readout told him he had operational turbojets. He let them warm a minute before running them up to 100 %.

Mach 3.1. Three times the speed of sound. The high-pitched roar of the turbojets was behind him, leaving the cockpit in relative quiet. Except for the slight whisper of the increasingly dense atmosphere sliding over the craft’s skin that penetrated the insulation of the cockpit.

And except for the toothy, under-the-breath whistle of Tony Munoz, working his way off-key through the “Colonel Bogey March.”

The California coast came up quickly, pretty inviting on an October afternoon. McKenna knew, though, that his view from eight miles up was considerably more scenic than the close-up reality. The beer cans, fried chicken wrappers, and french fries sacks could be distracting.

Sometimes he wondered how he had been so fortunate. He was being paid for this. Originally, after achieving his engineering degree from the Air Force Academy, McKenna’s sole objective had been to become a general. It seemed like the thing to be from a twenty-two-year-old’s perspective. Now, he didn’t give a damn if he never advanced beyond the silver eagles he wore on the right occasions. Generals didn’t get to fly much.

The MakoShark passed into the coastal Air Defense Identification Zone, the ADIZ, without a challenge from one radar site, civilian or military.

The explanation was simple enough. The MakoShark was invisible to radar.

Every facet of stealth technology had been utilized in her construction. The internal ribs of her wings and fuselage were cast of honeycombed carbon-impregnated fiberglass that reflected radar probes at odd angles, and not back to the radar transmitter. The skin of the craft was also carbon-impregnated plastic and was coated in a midnight blue paint containing microscopic iron balls which conducted electricity and deterred radar reflection. Instead of bouncing back, radar signals slithered around on the surface of the MakoShark. The radar cross section (RCS) was so slim that the craft had to be within five miles of a powerful conventional radar before she returned a signal the size of a California Condor, and that signal was weak enough to go unnoticed.

The turbojet engines were not directly behind the intake duct; they sucked their air supply from an upward-curving tunnel. In that configuration, the spinning turbine blades were diminished as radar reflectors. To limit the RCS additionally, the turbojet blades were not made of metal. They were plastic, combined with carbon fiber for strength. While some designers had experimented with engines made of ceramics — not detectable on radar — the MakoShark’s designers had elected to stay with the more reliable and higher output metal-encased engines, which were enclosed in a honeycombed structure that diffused and absorbed radar probes.

The jet engines were mounted nearer the forward end of long nacelles, and their exhaust was channeled slightly downward in another curving tunnel that was wrapped with tubing carrying Freon gas. The refrigerant cooled the exhaust considerably, so that by the time it exited the exhaust pipe, its infrared signature was practically nonexistent at seventy per cent throttle settings. Infrared tracking sensors just might pick up a small signal at ninety per cent throttle, and would at a hundred per cent.

The rocket motors were mounted inboard of the jet engines, in the same nacelles, and were also protected from radar by the honeycomb layer.