XCOR Lynx

Lynx

Mockup of Lynx spaceplane
Function	Manned suborbital launch and reentry
Manufacturer	XCOR Aerospace
Size
Stages	(none, fully reusable spacecraft)
Boosters
No. boosters	4
Engines
Thrust	2,900 pounds
Burn time
Fuel	LOX-Kerosene

The XCOR Lynx is a suborbital horizontal-takeoff, horizontal-landing (HTHL), rocket-powered spaceplane under development by the California-based company XCOR Aerospace to compete in the emerging suborbital spaceflight market. The Lynx is projected to carry one pilot, a ticketed passenger, and/or a payload above 100 km altitude. As of July 2015, the passenger ticket was projected to cost $150,000.

The concept has been under development since 2003, when a two-person suborbital spaceplane was announced under the name Xerus. According to a September 2015 report, the first flight of the Lynx spaceplane is likely to be in the second quarter of 2016 from Midland, Texas.

History

Xerus

In 2003, XCOR proposed the Xerus (pronunciation: zEr'us) suborbital spaceplane concept. It was to be capable of transporting one pilot and one passenger as well as some science experiments and it would even be capable of carrying an upper stage which would launch near apogee and therefore would potentially be able to carry satellites into low-Earth orbit. As late as 2007, XCOR continued to refer to their future two-person spaceplane concept as Xerus,

Lynx

The Lynx was initially announced on March 26, 2008, with plans for an operational vehicle within two years. In December of that year a ticket price of $95,000 per seat was announced. The build of the Lynx Mark I flight article did not commence until mid 2013 and, as of October 2014 XCOR claims that the first flight would take place in 2015. In July 2015 ticket prices increased by 50% to $150,000.

Passengers hoping to make flights in the Lynx include the winners from the Axe Apollo Space Academy worldwide perfume contest, and Justin Dowd of Worcester, Massachusetts, who won Metro International's Race for Space newspaper contest. As of December, 2015, Kayak.com was reportedly selling tickets for flights on the XCOR Lynx starting in 2016.

Description

The Lynx will have four liquid rocket engines at the rear of the fuselage burning a mixture of LOX-Kerosene, each engine producing 2,900 pounds-force (13,000 N) of thrust.

Mark I Prototype

• Maximum Altitude: 62 km (203,000 ft)
• Primary Internal Payload: 120 kg (260 lb)
• Secondary payload spaces include a small area inside the cockpit behind the pilot or outside the vehicle in two areas in the aft fuselage fairing.
• Composite LOX tank
• Mach 2 (1,500 mph) speed of ascent
• 4G re-entry loading

Mark II Production Model

• Maximum Altitude: 107 km (351,000 ft)
• Primary Internal Payload: 120 kg (260 lb)
• Secondary payload spaces include the same as the Mark I.
• Non-toxic (non-hydrazine) reaction control system (RCS) thrusters, type 3N22
• Nonburnite LOX composite tank

Mark III

The Lynx Mark III is the same vehicle as the Mark II with External Dorsal Mounted Pod: 650 kg (1,430 lb) and is large enough to hold a two-stage carrier to launch a microsatellite or multiple nanosatellites into low-Earth orbit.

Lynx XR-5K18 engine

The XR-5K18 is a piston pump fed LOX/RP-1 engine using an expander cycle. The engine chamber and regenerative nozzle are cooled by RP-1

The development program of the XCOR Lynx 5K18 LOX/kerosene engine reached a major milestone in March 2011. Integrated test firings of the engine/nozzle combination demonstrated the ability of the aluminum nozzle to withstand the high temperatures of rocket-engine exhaust.

In March 2011, United Launch Alliance (ULA) announced they had entered into a joint-development contract with XCOR for a flight-ready, 25,000 to 30,000 pounds-force (110,000–130,000 N) cryogenic LH2/LOX upper-stage rocket engine (see XCOR/ULA liquid-hydrogen, upper-stage engine development project). The Lynx 5K18 effort to develop a new aluminum alloy engine nozzle using new manufacturing techniques removes several hundred pounds of weight from the large engine leading to significantly lower-cost and more-capable commercial and US government space flights.

Airframe

It was reported in 2010 that the Mark I airframe could use a carbon/epoxy ester composite, and the Mark II a carbon/cyanate with a nickel alloy for the nose and leading-edge thermal protection.

Mark I build

The flight article Lynx Mark I is claimed as being fabricated and assembled in Mojave beginning in mid 2013. The cockpit of the Lynx (made of carbon fibre and designed by AdamWorks, Colorado) was reported as being one of the items that held up the assembly.

At the start of October 2014, the cockpit was attached the to fuselage. The rear carry-through spar was attached to the fuselage shortly after Thanksgiving 2014. At the beginning of May 2015, the strakes were attached to the airframe. The last major component, the wings, are expected to be delivered in late 2015.

Test program

Tests of the XR-5K18 main engine began in 2008.

As of February 2011, engine tests were largely complete and the vehicle aerodynamic design had completed two rounds of wind tunnel testing. A third and final round of tests was completed in late 2011 using a "1/60-scale supersonic wind tunnel model of Lynx."

As of October 2014, XCOR claimed that flight tests of the Mark I prototype would start in 2015.

Operations

NASA sRLV program

As of March 2011, XCOR has submitted the Lynx as a reusable launch vehicle for carrying research payloads in response to NASA's suborbital reusable launch vehicle (sRLV) solicitation, which is a part of NASA's Flight Opportunities Program. XCOR projects 110 km (68 mi) altitude in flights of 30 to 45 minutes duration, while carrying up to 140 kg (310 lb) internal—or 650 kg (1,430 lb) external—of research payload. Flights will provide up to three minutes of microgravity below 0.01 g.

Commercial operations

According to XCOR, the Lynx will fly four or more times a day, and will also have the capacity to deliver payloads into space. A Lynx prototype called Mark I was expected to perform its first test flight in 2015, followed with a flight of the Mark II production model twelve to eighteen months after. XCOR currently plans to have the Lynx's initial flights from the Mojave Air and Spaceport in Mojave, California or any licensed spaceport with a 2,400 meter (7900 ft) runway. Towards the end of 2015 or in 2016 the Lynx is expected to begin flying suborbital space tourism flights and scientific research missions from a new spaceport on the Caribbean island of Curaçao.

Because it lacks any propulsion system other than its rocket engines, the Lynx will have to be towed to the end of the runway. Once positioned on the runway, the pilot will ignite the four rocket engines and begin a steep climb. The engines will be shut off at approximately 138,000 feet (42 km) and Mach 2. The spaceplane will then continue to climb, unpowered until it reaches an apogee of approximately 200,000 feet (61 km). The spacecraft will experience a little over four minutes of weightlessness before re-entering the Earth's atmosphere. The occupants of the Lynx may experience up to four times normal gravity during re-entry. Once it has completed re-entry, the Lynx will then glide down and perform an unpowered landing. The total flight time is projected to last about 30 minutes. The Lynx is expected to be able to perform 40 flights before maintenance is required.

As of March 2011, Orbital Outfitters was designing pressure suits for XCOR use.

As of 2012, the successor to the Mark II may be a two-stage fully reusable orbital vehicle that takes off and lands horizontally.

Development cost projections

As of 2008, Mark I production was projected to cost US$10 million, and the Mark II around US$12 million.

See also

• Private spaceflight
• EADS Astrium Space Tourism Project
• Rocketplane XP
• SpaceShipTwo
• Blue Origin New Shepard
• XCOR EZ-Rocket
• XCOR Mark-I X-Racer

External links

• Lynx Suborbital Spacecraft Page
• Lynx Reusable Launch Vehicle Approaches Completion, AmericaSpace, November 2015.