Parallels between the historical development of combat missions for aircraft and the current development of such missions for spacecraft are becoming ever more exact.
In World War I, aircraft were first used for reconnaissance, then as the means of preventing it by shooting down the recce aircraft, then to provide air cover for them, and finally to deliver ordnance.
This pattern is now clearly evident in space systems as well.
US officials now openly regard space as "the fourth combat medium." This is the basic reason why space systems and space doctrine demand USAF's unflagging attention and will come to engross Air Force leaders in the years ahead.
The Reagan Administration set the pattern.
On July 4, 1982, President Reagan issued his National Space Policy, ordering up a comprehensive civil and national security space program. From it, all things began to flow.
Shortly thereafter, USAF established its Space Command to centralize and give focus to its proliferating space activities. It also expanded its space doctrine to accommodate a wider range of missions, including "force application" in and from space.
Last November, the President authorized a new unified command, the US Space Command, to be made up of all four military services. And then, last April, he set in motion a new study by the National Aeronautics and Space Administration and the Department of Defense. It will size up the nation's urgent need for new space-launching capabilities and attendant, advanced launching technologies.
In all considerations of what is happening or of what will happen in space, USAF predominates. This is abundantly clear in the US military space budget.
According to figures supplied by Air Force Space Command. the $11 billion that USAF has budgeted for space programs and activities in Fiscal Year 1986, to begin next October 1, accounts for seventy-nine percent of the entire DoD space budget for that fiscal year. The Army accounts for six percent, the Navy for four percent, and defense agencies, such as the Defense Communications Agency and the Defense Nuclear Agency, for eleven percent altogether.
Moreover, USAF's space-budget total does not include its share of the $3.7 billion proposed for the DoD-wide Strategic Defense Initiative (SDI) program in Fiscal Year 1986. That share is very large. USAF is in charge of most SDI technology development programs, many of which are pertinent to the Air Force's rapidly evolving space systems and doctrine.
USAF in Space
As reflected in the budget, Air Force activity in space is booming. It is summed up in this year's joint report to Congress by Dr. Thomas E. Cooper. Assistant Secretary of the Air Force for Research, Development and Logistics, and Gen. Robert D. Russ, who at the time of the report was USAF's Deputy Chief of Staff for Research, Development and Acquisition, as follows:
"Air Force objectives in space include pursuing a vigorous research and development program to give us future options in space, expanding to space those functions that can be better accomplished there, and developing an antisatellite system to assure our free access to space and to deter Soviet attacks against our satellites in orbit.
"Our plans include making our space systems—the satellites, the ground stations, and the communications links between them—more survivable from attack, improving the surveillance, communications, and navigation capabilities of our space systems, and increasing the robustness of our space system network by removing single [communications] nodes, procuring backup satellites, and reducing our dependency on overseas ground stations."
Moreover, said the report, USAF is concentrating on "doing more with each launch by deploying satellites with the capability to perform multiple missions, and with much longer operational lives."
In keeping with this, President Reagan recently authorized the Air Force to develop a powerful new booster rocket for launching payloads too big and heavy to be sent into space by any means other than the Space Shuttle.
USAF plans to buy ten of these Titan 34D7 rockets, called Complementary Expendable Launch Vehicles (CELVs), and to launch a payload on the first of them into transpolar orbit from Vandenberg AFB, Calif., in October 1988.
Air Force launching of payloads on the Shuttle from Vandenberg will continue. However, in making use of the CELVs as well, the Air Force expects to cut its launching costs and its risk of overdependence on the Shuttle as its only means of boosting extra-hefty military payloads into orbit.
USAF has also asked the Administration for permission to modify thirteen deactivated Titan II ICBM boosters for space launches from Vandenberg. It wants those boosters, which are much less powerful than the Titan 34D7s will be, to launch relatively small military satellites into near-earth orbits.
Weather satellites, for example, are so small that they look lost in the Shuttle's cavernous cargo bay. USAF needs to be able to launch such small satellites one at a time—as needed and when ready—and cannot afford to wait for a programmed Shuttle launch to accommodate several of them. Launching them singly on the Shuttle is decidedly cost-ineffective.
Given all such USAF stirrings on the space front, arguments that US production and deployment of antisatellite (ASAT) weapons would "militarize" space miss the point and have a hollow ring.
Space has been militarized, in effect, for nearly thirty years, ever since the first ICBM traversed it on a test flight and the first surveillance satellite was launched into it. Moreover, the Soviet Union has an ASAT weapon that former Secretary of Defense Dr. Harold Brown flatly described as operational in early 1978. First tested as far back as 1968, it is fully capable of destroying US surveillance satellites and others in low orbits. Land-based Soviet laser-weapon test installations seem capable of destroying—certainly they threaten—US satellites in higher orbits.
This raises a very scary prospect, for, in one way or another, US strategic and tactical forces have come to depend very heavily on a widening array of US satellites for their very ability to deter or to wage nuclear or nonnuclear war. There are said to be more than 100 such satellites in space at any one time.
Dependence on them is deepening with every tick of the clock. It has got to the point that the satellites are no longer regarded as merely "force multipliers" or as tools for "force enhancement."
Instead, affirms Gen. Robert T. Herres, Commander of USAF's Space Command and of the Aerospace Defense Command, the satellites are "becoming absolutely integral" to US weapons and forces on land, at sea, and in the air.
"Our high-tech edge over the Soviets is more and more satellite-dependent," General Herres declares. "Anybody who thinks we can plan national security into the next century without military capabilities in space has a bankrupt idea. And if those capabilities are so important, shouldn't we expect that they will be attacked in a war? Of course."
Data from Space
Surveillance satellites, ever more capable, routinely pass on streams of data that enable the National Command Authorities (NCA) and strategic and tactical commanders to stay in a heads-up mode. They are the main means of policing arms-control agreements and for keeping tabs on movements of military forces anywhere in the world. They also are said to have become so proficient—in their coverage and in their real-time responsiveness—that they can be used for actual selection of tactical targets.
Old-time navigation satellites like those in the Navy's Transit system can at best enable a warship skipper to fix his position within a radius of miles. The new US Navstar Global Positioning System (GPS) constellation of navigational satellites will do a whole lot better than that.
In providing three-dimensional position and velocity data, GPS can fix the whereabouts of the ship captain and those of bomber, fighter, infantry, and armor commanders within sixteen meters. Thus, it is crucial to their disposition of firepower.
The GPS system will provide worldwide navigational coverage for US forces near the end of 1988, when all eighteen GPS satellites are expected to be operating in their orbits. Ten GPS developmental satellites have already been launched, and eight of them are being used in the GPS test program.
GPS will also be a prime means of precise navigational updating for future submarine-launched ballistic missiles.
Critical to everything military are the communications satellites, relay-station switchboards in the sky for the far-flung US military forces.
It is estimated that from one-half to three-fourths of all US overseas military communications are routed via space relays. The malfunctioning or destruction of communications satellite constellations could mean sudden disorder and death on battlefields, at sea, and in the air.
Airborne weapon systems that rely on digitalized maps in their guidance computers also owe a great deal to the geodetic, terrain-mapping satellites. Weather satellites are indispensable scouts for battle planning and battle management.
Odd as it now may seem, the long-term wartime survivability of military satellites was not considered all that important until the beginning of this decade. It became important, direly so, when the US moved away from its premise that a nuclear war would be a bam-bam cataclysmic spasm of all-out attack and retaliation and began planning instead for the eventuality of a protracted nuclear war.
In 1980, having reviewed US strategic policy, President Carter issued Presidential Directive (PD) 59. It codified what was called the US "countervailing" nuclear strategy, actually a refinement of a strategy that had been evolving ever since Dr. James R. Schlesinger's strategically hard-nosed stewardship of the Department of Defense from 1973 to 1975.
The strategy was summarized by Dr. Brown, Carter's Secretary of Defense, in his final report to Congress in January 1981. The report made it clear to the Soviet Union that "no course of aggression by them that led to the use of nuclear weapons, on any scale of attack and at any stage of conflict, could lead to victory, however they might define that victory."
It went on to say: "Besides our power to devastate the full target system of the USSR, the United States would have the option for more selective, lesser retaliatory attacks that would exact a prohibitively high price from the things the Soviet leadership prizes most—political and military control, nuclear and conventional forces, and the economic base needed to sustain war."
Among the requirements for implementing this strategy, Dr. Brown enumerated "flexibility of weapons and targets" and "escalation control." His umbrella requirement was "survivability of nuclear forces and their supporting C3I capabilities."
Satellites had long since become the essence of such capabilities. Formerly, they had been deemed necessary only to give warning of a nuclear attack and then to play key roles in the launching and execution of an all-out retaliatory strike, after which their reason for existence would end.
New Role for Satellites
Now, with the countervailing strategy, they would be called upon to keep on operating in support and management of US thrusts and parties in a drawn-out nuclear duel.
They were simply not up to that. They had no shielding against the electromagnetic effects of nuclear explosions or against the intense heat of lasers and the electronics-disrupting penetration of neutral particle beams. They could not maneuver out of the way of a Soviet ASAT weapon that might catch up with them via radar to kill them with the shrapnel from its remotely controlled self-destruction.
US communications and early-warning satellites range in faraway geosynchronous orbits above the equator, well beyond the reach of the low-flying, coorbital Soviet ASAT interceptors. But US surveillance satellites coursing through space on much lower transpolar orbits—so that the earth rotates roughly perpendicular to their flight paths and thus keeps passing under their lenses—are indeed vulnerable to the Soviet ASATs.
US officials estimate that those ASATs can reach targets up to 3,000 miles high, but are probably intended for top-priority US satellites at lower altitudes. Many US surveillance, weather, and navigation satellites are said to orbit, some of them quite eccentrically, at less than 600 miles about the planet. There may be a score of such satellites in space at any one time.
The Soviet "hunter-killer" ASATs, which have been derided as primitive by some opponents of the US ASAT program, are nonetheless clearly capable of nailing those US satellites, as one demonstrated against a Soviet target satellite in a test flight just three years ago. (For more on the US and Soviet ASAT programs, see "A Dozen Anti-ASAT Fallacies" on p. 78 of this issue.)
Thus, the Soviet ASATs are serving the same purpose vis-à-vis US spacecraft orbiting in low-to-medium orbits as the Soviet surface-to-air missiles are serving against US and allied fighter and ground-attack aircraft—closing off their operating regimes, eliminating what used to be their sanctuaries.
What's more, the Soviets now have two ground-based facilities for testing high-powered lasers that could be brought to bear against US satellites in much higher orbital planes, such as early-warning satellites and communications satellites operating in support of US strategic forces. And the Soviet Galosh ABM missiles around Moscow could play hob in high space with nuclear bursts.
The Soviets have been moving in other ways too—such as their long, hard work on space stations and on adapting their cosmonauts to protracted periods of existence in orbit—to make space a full-fledged military medium managed by men up there.
Protecting Our Assets
All this adds up to the reason why the Reagan Administration immediately went to work at strengthening and protecting US space assets—an effort that undergirds each and every continuing, new, and future US space program.
Right from the start, the Administration went full bore on the US ASAT development program. Begun by President Ford, it had languished under President Carter, who was once described as not wanting to see "even so much as a peashooter in space"—an attitude that began changing once his Secretary of Defense demonstrated to him that the Russians had ASATs that worked.
The US ASAT weapon is a two-stage rocket with a drum-shaped, heat-seeking Miniature Vehicle (MV) nonexplosive warhead on its snout. It is taken aloft on an F-15. Once released by the aircraft, which was vectored to the launch point, the weapon's modified Short-Range Attack Missile (SRAM) first stage and its Altair rocket second stage boost it into and through space.
Closing on the target satellite via "direct ascent" (in contrast to the much slower coorbital catchup technique of the Soviet ASAT), the MV separates and is maneuvered to its target by small thrusters positioned around its circumference.
It homes on the target satellite's "black body radiation" by virtue of signals interplay between its heat-seeking sensor and its tiny on-board computer. It kills by striking the target at tremendous closing speed (satellites must orbit at speeds of at least 17,000 miles per hour, or they succumb to gravity).
F-15s assigned to carry ASAT weapons will be stationed at Langley AFB, Va. and McChord AFB, Wash. They will be under the command and control of the Space Command/Aerospace Defense Command Space Defense Operations Center (SPADOC) and will receive mission profiles from and be vectored by the ASAT Mission Control Center at Cheyenne Mountain, Colo., prior to takeoff.
USAF has conducted two tests of its ASAT weapon. The first was limited to a workout (successful) of the weapons booster and booster-guidance systems and was directed against a point in space, not against a target satellite. The second test, a partial success, reaffirmed the results of the first and gathered limited data about MV performance.
Tests and Arms Talks
A test against a target satellite will come soon. Congress forbade any such real-life testing until ASAT arms-control negotiations with the Russians got under way or President Reagan convinced the lawmakers that he is earnest about conducting such negotiations.
Given the good-faith evidence of the current Geneva arms-control talks between the US and the USSR, it is likely that USAF will be permitted to resume testing its ASATs this summer—and this time against an orbiting target.
The Air Force plans about ten more ASAT tests. It has set the ASAT IOC for the late 1980s. The exact date is classified.
As the Administration's national space policy directive of 1982 made clear, the Air Force is developing its ASAT not only to defend US satellites against attacking spacecraft but also—just as important—to take out Soviet satellites during wartime.
High on the list of such prospective Soviet target satellites are those constantly reconnoitering the oceans and providing targeting data for Soviet use against US carrier battle groups. Such information is vital to Soviet bombers overflying the oceans with long-range antiship cruise missiles and to Soviet attack submarines also thusly armed.
In fact, the Soviets have developed a comprehensive targeting system in space, and their satellites too are now regarded as integral parts of their air, land, and sea weapon systems and forces.
ASATs are often thought of in the context of a nuclear war. They would be just as important, however, in a nonnuclear war because surveillance satellites, their prime targets, are important to the prosecution of such a war.
The US SDI program has obvious antisatellite overtones. Clearly, any space-based defensive system capable of coping with welters of boosters and warheads would also be capable of picking off satellites, which would be "sitting ducks" by comparison.
SDI in Context
The SDI program is the defensive segment of a much broader strategic whole.
The Reagan Administration retained Mr. Carter's PD-59 as the basis of its own strategic policy, but swiftly set about giving it substance. The basis of this was the strategic modernization program that Mr. Reagan expounded in October 1981.
That program is probably best known for its emphasis on such "countervailing" weapons as the MX ICBM and the B-1B bomber. Its top priority, however, was—and is—to modernize the nation's C3I assets and make them more muscular and much less vulnerable.
C3I has become virtually synonymous with space. Consequently, DoD, with the Air Force as its principal agent, is concentrating on hardening and dispersing satellites and their ground nodes against nuclear attack—against so-called "EMP coupling." wherein a nuclear burst generates an electromagnetic pulse that "couples" into electrical circuits and burns them out.
There are several ways to accomplish such hardening—by incorporating filters, surge arresters, Faraday cage contrivances, and the like. New generations of US satellites, such as the Milstar and the DSCS (Defense Satellite Communications System) III varieties, are designed with resistance to EMP in mind.
As one Air Force general puts it, however, "The real quantum steps in making satellites more survivable are yet to come." They will cost a bundle of money.
Among those steps will be the shielding of satellites (including, and notably, the SDI battle-station types) against attacks by lasers and particle-beams and providing some satellites with enough autonomous thrust to enable them to maneuver out of the way of orbital-interceptor ASATs (this would not work against a speed-of-light laser attack). These satellites will be equipped with sensors that will see those interceptors coming in plenty of time.
The Weight Premium
The problem—a big one—with those methods is that they add weight to the satellites. Weight is at a premium on all spacecraft. As Air Force officials explain it, self-defensive additions to satellites almost always compromise their ability to execute their missions, given their stringent overall weight constraints.
This is why the SDI program puts great emphasis on cutting the cost of putting every pound of its prospective spacecraft into orbit.
The weight problem is compounded by the fact that new generations of "multipurpose" satellites are being built and designed to do more than one mission. This means great demands on their performance.
In spacecraft, as in aircraft, weight translates directly into cost. Moreover, it translates into bulk, and this, in years to come, will complicate the satellite-launching process.
Such a prospect explains why the US will probably have to resort to booster rockets much more powerful than those now used for depositing military satellites into space.
Satellites are loaded with electronic subsystems, which also add weight. Thus, one saving grace in the weight-performance tradeoff dilemma lies in the remarkable advancement of microelectronics technology—best exemplified by the very-high-speed integrated circuits (VHSICs) now entering production for USAF, the Army, and the Navy.
The VHSIC semiconductor chips are expected to be highly reliable and to process signals and data at dazzling speeds. If they live up to their billing (with even more proficient varieties in the offing), they promise not only to revolutionize the avionics of aircraft, such as USAF's Advanced Tactical Fighter, but also to provide satellites with extensive flight-control capability while actually reducing the weight of their electronic innards.
Just a few tiny VHSIC chips on a thin, lightweight circuit board can do signal-processing and data-processing jobs that now require many comparatively massive black boxes. Such compact circuit boards will also require far fewer wiring connections between the chips and the microcomputers they constitute, thus greatly reducing the chance of failures inherent in such connections.
Moreover, they can be installed in aircraft and spacecraft so copiously as to back up one another in case of failures (which they themselves will diagnose), and the microcomputers comprising them will be conducive to the incorporation of artificial-intelligence software.
All this will take satellites a long way toward fault-tolerance and autonomy. In turn, it is expected to lead to far less dependence on vulnerable and expensive ground stations that now must do the command-and-control data and signal processing for the satellites.
C2 for Space
The Air Force now maintains command and control of spacecraft through its Satellite Control Facility (SCF), a network of seven remote tracking stations around the globe that are interconnected through USAF's Satellite Test Center (STC) at Sunnyvale AFS, Calif. It controls military missions of the Shuttle from facilities at NASA's Johnson Space Center, Houston, Tex.
Both are highly susceptible to sabotage and, in the case of the STC, to earthquakes, to say nothing of surprise attack by submarine-launched ballistic or cruise missiles from the Pacific. Moreover, the STC's computer facilities leave something to be desired.
To relieve STC's work load, USAF is moving as fast as possible to build its new Consolidated Space Operations Center (CSOC) near Colorado Springs, Colo., on the eastern side of the Rockies. Scheduled to begin operating next year, the CSOC will share the command and control of some critical military space missions with the STC, and each will control certain satellites independently, backing up one another as well.
In yet another major construction project pegged to assuring routine access to space, DoD is building a Shuttle launching and landing facility at Vandenberg. Its purpose is to launch Shuttle satellite payloads into transpolar orbits, something that cannot be done effectively from Cape Canaveral, Fla. Booster rockets for transpolar launches from Canaveral would fall on land, not into the ocean.
The coastal locations of Vandenberg and Canaveral are also worrisome to US space planners. Privately, some of them predict that the new NASA-DoD study of what the US needs to prepare to do in space will culminate in a recommendation for more secure, inland Space Transportation System bases.
Ensuring the security of space-oriented systems also means protecting the streams of data and signals that pass between the spacecraft and their air, land, and sea terminals as well.
It serves no purpose to have a fully functioning set of communications satellites transmitting messages to strategic or tactical forces if those messages are jammed—and it is almost certain that an enemy would try jamming before, or even as, he attacks satellites and terrestrial stations.
This is why the DSCS III communications satellites, now building up to their full orbiting complement, and the Milstar strategic and tactical communications satellites, scheduled for initial deployment later in this decade, are so important.
The DSCS III system, now augmenting but later to replace the DSCS II system, was developed to provide superhigh frequency (SHF) communications for secure-voice and high-data-rate transmissions.
USAF officials are satisfied that the system meets requirements as bearer of a wide range of traffic—military command and control, crisis management, early-warning detection-data relay, treaty monitoring, surveillance information, and diplomatic messages. The DSCS III satellites also have it over their forerunner DSCS II satellites in number of channels, flexibility, and counter-countermeasures capability.
The DSCS III system's flexibility has to do with its geographic range, meaning the satellites' scope of coverage and the mobility of their ground stations.
Each of the six satellites in the system, including "spares," has a "footprint" covering approximately one-third of the globe. A full-up DSCS III ground terminal can be carried by a C-5 airlifter and can be made available to US forces anywhere just as fast as the airlifter can reach them. Four DSCS III satellites are expected to be on station in geosynchronous orbit by the end of next year.
The problem with those big broad footprints is that somewhere in nearly all of them lies a potential adversary who could try jamming them.
USAF officials are confident that it would be impossible to take all, or even much, of the DSCS III system off the air by means of jamming. But the Soviets are obviously working toward that end. So it's probably only a matter of time before they learn how to jam the DSCS III satellites, and this is why the Pentagon is already considering the development of a follow-on DSCS satellite system for possible deployment in the twenty-first century, or maybe a little before.
The concepts, techniques, and technologies of the Air Force's communications satellites capable of operating in intense jamming environments are developed in USAF's Advanced Space Communications program. It deals, for example, in laser communications and in satellite internetting.
From Strats to Milstar
Out of that program several years ago came USAF's proposal for a Strategic Satellite System (SSS), made up of so-called "Stratsats," to replace the Air Force Satellite Communications (AFSATCOM) system.
AFSATCOM consists of transponders aboard the Navy's Fleet Satellite Communications (FLTSATCOM) satellites in geosynchronous orbits and is linked to USAF Satellite Data System (SDS) satellites in transpolar orbits. All serve strategic forces.
The idea was to have only a few Stratsats provide global coverage from their "parking" positions five times higher than geosynchronous orbit, in what is called hyper-geosynchronous orbit.
SSS funding was denied by Congress during the years of the Carter Administration, however, and so the Air Force turned to the Milstar system. instead.
Milstar is critical to the success of the Administration's strategic modernization program and was assigned the highest national priority—far very good reasons.
It represents DoD's most ambitious satellite communications program to date. Scheduled to be fully deployed around 1993, it will consist of a constellation of satellites circling the earth once a day at various inclinations relative to the equator. It is said that some will be "parked" in near-geosynchronous orbit as well.
All will be linked with a superabundance of air, land, and sea terminals of strategic and tactical forces. The Air Force is developing the Milstar system satellites, system control equipment, and airborne terminals. The Army and the Navy are developing ground and seaborne terminals, respectively.
For USAF, the Milstar linkups will be the assured means of bomber, fighter, tanker, airlifter, and radar aircraft units staying in touch with one another, and with commanders at all levels, at all times anywhere in the world.
The entire system is being built from scratch for robustness, survivability, and security of its communications. In this, it will feature crosslinks and such techniques as frequency hopping and time shuffling and will be hardened against nuclear and laser attack.
Its extremely-high-frequency (EHF) voice and data transmissions promise to be almost impossible to jam in the context of the current state of the art.
Testing of Milstar-capable EHF subsets was scheduled to begin aboard two new FLTSATCOM satellites next year. Once the Milstar system is fully operational, the AFSATCOM transponders on those satellites will be phased out. The Milstar and DSCS communications constellations and the Navstar navigation constellation will contain a sufficient number of satellites so that some in each can orbit idly as "spares" and then be switched on if necessary.
This begins to address a tough decision confronting the Air Force more and more—how best to "reconstitute" its fleets of satellites after too many take hits or are otherwise neutralized during war.
The "spares" method—also called "on-orbit storage"—seems to be the favorite. In its budget projections for future years, USAF is looking to provide increasing amounts of money for such storage in space.
But USAF would also like to have much greater capability for launching crucial "warfighting" (as contrasted with "deterring") satellites in short order as wars or crises demand.
This need is related to USAF's insistence on having the assurance of routine access to space independent of the Shuttle and is why the White House authorized its purchase of the ten CELVs.
But even those big boosters take a lot of time and involve much costly manpower in preparation for launching of satellites. All the while they are vulnerable on the ground.
There are several ways of confounding would-be attackers of satellites.
One is deception, which can take several forms. Another is proliferation—launching the varieties of smaller satellites, such as many surveillance, communications, and weather satellites, in bunches for dispersal in space, thus vastly complicating any attacker's target-selection process.
The Soviets are longtime users of this "salvo" technique, as they have demonstrated during such tense times as the Middle East and Falklands wars. They are said to have popped sixteen satellites into space in a big hurry to keep track of what was going on around the Falklands.
Some space experts in the Air Force, the Department of Defense, and the aerospace industry believe that manned spaccplanes capable of taking off from runways would be just the ticket in helping to solve the problem of reconstituting, and maintaining sets or constellations of satellites on short notice.
Enter the Transatmospheric Vehicle (TAV) and all such horizontal-takeoff or single-stage-to-orbit spaceplanes.
Those concepts excite many officials. They have quite a way to go, however, before they are transformed into hardware, if ever.
Even so, several high-ranking Air Force officers have told this magazine that, as one put it, "we'll get a TAV sooner or later because we'll probably have to have it."
Daily Report: Read the day's top news on the US Air Force, airpower, and national security issues.
Daily Report: Read the day's top news on the US Air Force, airpower, and national security issues.
Tweets by @AirForceMag