High-Altitude Aircraft

High-altitude aircraft offer the opportunity to experience other aspects of space than the weightless experiences provided by parabolic aircraft. Passengers in a flight to 60,000 feet and above would see the curvature of the earth below and the dark sky of space above. They would see expansive views of whatever region they were flying over, above most of the clouds.

Some have pointed out that much of this can be experienced with a Concorde flight at 50,000 feet. Since the Concorde is viewed as an economic failure, in the sense that it does not pay its full costs (the French and British governments absorbed the development and manufacturing costs), but only the direct operating costs, that this means that there is no money to be made in a high-altitude tourism venture. This argument is flawed on at least two grounds:

First of all, the Concorde experience is not exactly what would be provided in a high-altitude joy ride--the windows, for the seats that have them, are rather small, most of the flight is over the ocean, and fifty-thousand feet may not be sufficiently high to offer the full experience. Since the view is the main attraction of the activity proposed here, one cannot draw any conclusions about the demand for such an activity from Concorde flights.

Second, Concorde was a financial disaster not because it is an unpleasant or even uninteresting flight experience or because it had no market—it was a financial disaster because it had high development costs to amortize over a market that was primarily a transportation market-- one limited by its high price and its inability to fly routes over land or over the Pacific, for reasons of sonic boom and short range capability. A tourism vehicle might have a limited market as well, but it's quite conceivable that it could make money with that market, if it were appropriately designed to specifically address it.

Four candidate aircraft for such an experience have been identified--three government-developed airplanes (though some instances of them may be privately owned), and one privately-developed aircraft.


This Lockheed creation is the highest-performance aircraft ever built--it holds both altitude and speed records. As an example of its performance, the Blackbird cruises above Mach 3 (three times the speed of sound). It has set numerous speed and altitude records including the following:

New York to London 1 hr., 54 min., 56.4 sec.

London to Los Angeles 3 hrs., 47 min., 35.8 sec.

Los Angeles to Washington D.C. 1 hr., 4 min., 20 sec.

West Coast to East Coast U.S. 1 hr., 7 min., 54 sec.

St. Louis to Cincinnati 8 min.

Kansas City to Washington D.C. 26 min.

The top speed was in excess of 2,193 miles per hour at an altitude of over 85,000 feet. That breaks down to about 35 miles per minute. The aircraft measures 99 feet by 55 feet at a height of 18 feet. It has an empty mass of 60,000 lbm. and masses 120,000 lbm. when fueled.

For a passenger, both the speed and the altitude would provide a considerable and unique thrill. The altitude is achievable in Russia in a Mig-25, but not the speed, and not for the length of time offered by the SR-71. It would be a comparatively mild ride from a g-force standpoint.

Unfortunately, while it is the queen of all high-performance aircraft, it is now a hangar queen. The Blackbird was retired by the U.S. Air Force in 1990 after twenty-five years of service. Several of the planes were transferred to NASA for research and development and for tests that involve high altitude, speed and thermal conditions. None are currently operating, but two are stored in flying condition. It is estimated that it would require two million dollars to reactivate them. This would consist mostly of crew recertification. For the purposes of this study, we would have to use a two-seat version, either a trainer (with dual controls) or one with a rear seat for the Reconnaissance Systems Officer (RSO). NASA's two flyable aircraft include one of each.

In addition to the recertification costs, there are other issues and cost issues associated with using this aircraft. The fuel is unique in that it has a high-performance kerosene base (JP-7) and has to be ignited by a catalyst, tetraethyl borane. There is only enough left in existence for another fifteen flights or so (perhaps ten of which would be required to get pilots current again). So unless a new batch of fuel is ordered from Atlantic Richfield (for which a line would have to be restarted), there would be at most five flights available for passengers after return to operational status. Also, a pressure suit would have to be purchased or rented for the passenger (these cost on the order of a hundred thousand dollars). Russian suits could be procured at lower cost, but would not be interface compatible with the aircraft flight equipment. Including the two million in startup, and the ten flights for recertification (at a hundred thousand dollars per flight hour), each of those five flights would probably ultimately cost over a million dollars apiece.

There is probably sufficient demand for such a flight at that price, but the politics will remain a barrier, absent clear policy direction to make it happen. The Air Force still has very proprietary feelings toward the aircraft, and they are considered to be on loan to NASA. While no one would formally admit it, it is clear that having NASA use them was a means of maintaining availability of the asset to the DoD for reconnaissance, should they be needed, despite the official policy to retire them. There would undoubtedly be a great deal of resistance in some Defense quarters to using it for tourist joyrides.

However, there might be an opportunity to leverage this desire to retain the vehicle's capabilities, by proposing that the fleet be privatized, but remain available to the services (and NASA) for emergencies, similar to the Civil Reserve Air Fleet. Unfortunately, the spares (many of which are no longer manufactured, and available only on old blueprint at the Lockheed-Martin Skunk Works) and fuel situation are such that maintaining a fleet of such aircraft will probably be beyond the financial reach of a private concern, even with high-paying passengers.

Should such a program be created, the main purpose of it would be to demonstrate market and pathfind political, regulatory and insurance issues—it is unlikely that any useful medical data would be gained (at least in terms of later space tourism experiences).

U-2 (ER-2)

According to the Ames Research Center web site, "the Lockheed ER-2 was developed for the National Aeronautics and Space Administration (NASA), to serve as a high-altitude scientific research aircraft. The ER-2 designation was first applied to NASA's version of the U-2C model. NASA has since acquired and used the U2-R or TR-1 model, but has retained the ER-2 descriptor. The ER-2 differs from the U.S. Air Force's U-2 in the former aircraft’s lack of defensive systems, absence of classified electronics, completely different electrical wiring to support NASA sensors, and, of course, a different paint scheme.

The ER-2 is an extremely versatile aircraft well suited to multiple mission tasks. The ER-2 is thirty percent larger than the original U-2 with a twenty-foot-longer wingspan and a considerably increased payload over the older airframe. The aircraft has four large pressurized experiment compartments and a high-capacity AC/DC electrical system, permitting a variety of payloads to be carried on a single mission. The modular design of the aircraft permits rapid installation or removal of payloads to meet changing mission requirements. The ER-2 has a range beyond 3000 miles (4800 km); is capable of long flight duration and can operate at altitudes above 70,000 feet (21.3 km) if required. Scientific instruments flown aboard the ER-2 can be mounted in various payload areas. On a single flight, the ER-2 can carry over one ton of instruments to altitudes above 65,000 feet, and outside 95% of the Earth's atmosphere."

This aircraft would not be as exciting or have as much demand as an SR-71. It flies at a lower altitude (though still much higher than any commercial airliner) and it is subsonic. On the other hand, this aircraft would be much more affordable, since it is current, and has a specified operating charge from Dryden of $6000/flight hour. However, it is not designed for passengers (though there is an interesting precedent, in that Joan Lunden, one of the hosts of the ABC network morning news show, took a ride in a U-2 a few years ago).

Putting a passenger in one of the NASA aircraft would involve removing equipment from the main equipment bay and replacing it with a standard ejection seat. As in the case of the SR-71, a pressure suit would be required. These modifications might cost on the order of a hundred thousand dollars, so several flights would be required to amortize the costs of this down to something reasonable (a few tens of thousands of dollars) per flight.

This is probably a more politically feasible project, because of the increased availability of the aircraft, the fact that it is relatively obsolete for military purposes, and much more operable. The Joan Lunden precedent would help, and it could serve as a test bed for a "Ship's Company" type of venture, in which a wealthy individual would charter a corporation to do flight research, purchase services from NASA at the going rate, and name himself as the researcher. While the aircraft are in use much of the time for various NASA and other government agency research projects, there are some "dead times" during which someone could use it if they were convenient to Dryden in Southern California and could go on short notice (somewhat akin to "weekend specials" offered by some airlines).

Again, such a flight would serve more as a precedent than offer any useful physiological data.


The RB-57F was the result of a early-1960s program to produce a virtually new high-altitude reconnaissance aircraft out of the Martin B-57 "Canberra" bomber. The General Dynamics Corporation had a contract for the maintenance of the RB-57D aircraft, and in 1962, with wing spar problems having grounded most of the RB-57D fleet, the USAF approached General Dynamics to see if it would be possible to make a new reconnaissance aircraft out of the B-57--one with better all-round performance, higher payload capacity, and in particular an extended fatigue life. In October of 1962, the Fort Worth Division of General Dynamics was given a contract for the development of two redesigned aircraft under the designation RB-57F.

The wing of the RB-57F was an entirely new, three-spar structure with a span of 122 feet. Extensive use was made of honeycomb sandwich panels, which had originally been developed by Convair for the B-58 Hustler supersonic bomber. All of the fuel was carried inside the wings outboard of the engines. The large wing had a marked anhedral, and had a set of ailerons inset at mid-span that were supplemented by spoilers. All control surfaces had tightly sealed gaps in order to reduce drag, and there were no wing flaps. The aircraft was fitted with larger vertical tail surfaces. These surfaces were twice as large as those of the standard B-57.

The RB-57F was powered by a pair of 18,000 lb-thrust Pratt & Whitney TF33-P-11A turbofans, which gave the RB-57F more than twice the power of its predecessors. In addition, provision was made for a 3300 lb-thrust Pratt & Whitney J60-P-9 turbojet housed in a detachable pod underneath each wing. These auxiliary engines did not have starters, and were air-started after takeoff after windmilling up to 12 percent rpm. They remained at idling RPM up to 32,000 feet altitude, where throttling control started becoming effective. Full throttle could be used at altitudes above 40,000 feet. The J60s added approximately 2500 feet to the maximum ceiling. However, the J60s could be removed for maximum range missions.

There were four underwing hardpoints, all of which could be used to carry external stores when the turbojets were not mounted. The RB-57F could carry a two-ton HTAC high-altitude reconnaissance camera. Special ELINT/SIGINT equipment could be carried in the modified nose and in the plastic wingtip sections.

The crew was two, and the cockpit layout was the same as that of the standard B-57. The cockpit was provided with a modified Lear MC-1 autopilot.

The first RB-57F flew on June 23, 1963. Such were the extent of the modifications that new serial numbers for fiscal year 1963 were assigned to the modified aircraft. Many were used by the Air Force for reconnaissance, often at altitudes of up to 65,000 feet. The Air Weather Service bought some, which were designated WB-57F in 1968, for atmospheric sampling and monitoring of nuclear tests, and research into airborne laser equipment.

Many of them have since been purchased privately as they were surplused by the military, and been given "N" numbers. It would be possible to provide high-altitude rides in this aircraft. While certifying it for commercial flight would be very difficult, if not impossible under current regulations, several have been certified for experimental flight, and so could be rented for the purpose of "research." Flight costs would be fairly low, relative to the NASA planes already discussed—perhaps a few thousand dollars per hour. A passenger would either ride in the copilot seat, or a passenger module for multiple passengers could be constructed, with a plexiglass bottom, to hang in the bomb bay (doors open) as a "glass-bottom" high-altitude airplane. If the module had an auto-deploy chute, it could also be used as an ejection pod in an emergency. If it were designed to interface with Russian flight suits, this could result in additional cost savings.

It would be a noisy ride, but like the other aircraft, mild in g-rating, with little benefit for medical research. Of much more interest would be the precedent for opening up the FAA to allow passengers in more unconventional private aircraft (as in the parabolic flight case).

Proteus (http://www.scaled.com)

The last candidate for high-altitude passenger flight is the Proteus. According to the Scaled Composites' (its developer) web site, this is planned as a "twin turbofan high-altitude multi-mission aircraft, powered by Williams International FJ44-2E engines. It is designed to carry payloads in the 2000-pound class to altitudes above 60,000 feet and remain on station up to fourteen hours. Heavier payloads can be carried for shorter missions. It is intended for piloted as well as for UAV missions. Potential missions for Proteus include telecommunications, reconnaissance, atmospheric research, commercial imaging, and space launch."

It should be noted that the primary space transportation mission envisioned by Proteus’ inventor, Burt Rutan, is as the first stage for a suborbital space tourism vehicle, whose first mission will be to win the X-prize.

While the Proteus is not a high-speed aircraft (in fact it is probably the lowest-speed aircraft of any discussed in this report, because its primary mission is to simply orbit a local area at relatively low cost), it has several advantages over the government aircraft already discussed. First of all, it is an aircraft neither developed nor owned by the government, so no federal permissions are needed to use it, other than FAA approval. Second, it was designed as a commercial aircraft, in which operating cost was a fundamental design driver. It can thus be expected to offer much lower costs for space tourism experiences (though perhaps without some of the "right-stuff" mystique offered by the others). Because of its low-power jet engines, it will provide a very quiet, and much more pleasant ride than the military vehicles, offering an experience more similar to an extremely high-altitude sailplane.

On the downside, it won't be as thrilling, because it is slower, and less noisy. However, for people who simply want to view the earth from on high, and space from its edge, it could offer a very euphoric, perhaps even transcendental experience.

Cost estimates are not available at this writing, but the author would be surprised if rides couldn’t be offered (assuming sufficient demand) for prices well under ten thousand dollars.

Like the other atmospheric non-parabolic aircraft, it will provide little information in the way of medical issues, but it will serve as a useful regulatory pathfinder for privately-developed space passenger vehicles to a limited degree. The degree is limited by the fact that, like parabolic aircraft, it will remain regulated by FAA/AVR, rather than AST, as a space transportation vehicle would be, at least until it is actually employed as the first stage of a suborbital vehicle, as Burt intends. It will differ from the B-57 case in that it probably will be certified for commercial applications, though not necessarily to operate under Part 135 for passenger transport.

Russian Aircraft

One other category of atmospheric trips for passenger use, which in fact is currently being offered in Russia by Incredible Adventures, are flights in high-performance fighters. One of these, the Mig-25, can offer a very thrilling trip to the edge of space, as it zooms up to 80,000 feet or higher. Unfortunately, past attempts to bring such aircraft to the United States to offer similar passenger services here have been unsuccessful, because of FAA restrictions. Thus we face the irony that the formerly communist Russia seems to be more oriented to the space tourism maket than the supposedly capitalist United States. Any legislative or policy changes made with the intent of encouraging public space travel in the U.S. should consider this situation as another area for rethinking current FAA policies. This will be addressed further in the recommendations.

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Go on to suborbital trips.

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