Virgin Galactic is holding to its plan to put its first fare-paying passengers into suborbital space in 2014, and expects to be armed with a US Federal Aviation Administration operating licence during the first quarter of the year.

Addressing the ninth annual space conference at Rutherford Appleton Laboratory at Harwell, near Oxford, chief executive George Whitesides also promised imminent news regarding the company’s plans to offer air-launches of commercial satellites or scientific payloads from late 2015. The company, he said, has made significant headway on the liquid-fuel rocket it will use for the LauncherOne vehicle, and promised an update “in a few weeks”.

Whitesides also reiterated boss Richard Branson’s promise of starting commercial passenger operations in 2014, made back in October just after the company’s SpaceShipTwo rocketplane made its second powered flight, from its test base in Mojave, California.

Drop-launched from 52,000ft (16km) by its dedicated, twin-fuselage WhiteKnightTwo carrier aircraft, that flight marked the programme’s second in-flight ignition of the RocketMotorTwo engine, and second supersonic flight – during the 20s motor burn, SpaceShipTwo reached Mach 1.43 speed and 69,000ft altitude.

In operation, the plan will be to reach just beyond 100km altitude as fuel runs out to give six passengers about 6min of weightlessness on a parabolic path just above the atmosphere. In the time between engine shut-down and re-entry, passengers will experience a sensation similar to the microgravity experienced by astronauts in full orbital flight, and be free to move about the cabin, which is a fully pressurised shirt-sleeve environment.

Whitesides did not elaborate on further test flight plans or nail down a likely start of commercial service beyond “2014”. The company has been proceeding through development with extreme caution, and was at one time understood to be shooting for first commercial service in 2013.

Virgin Galactic is thought to have about 600 people signed up to fly, having made deposits or even paid the full $250,000 fare. As Whitesides observed at the Appleton conference, the total number of people who have flown in space to-date, starting with Yuri Gagarin in 1962, is just 542.

One of Virgin Galactic’s many dreams is to dramatically increase that very small number of people who have seen the Earth from space – both because it may turn out to be good business, and because, as Whitesides repeated in Harwell, people who have seen the planet from such a dramatic vantage point will hopefully feel a new sense of stewardship for it.

Virgin Galactic dates to Branson’s decision to sponsor Scaled Composites’ successful 2004 bid for the $10 million Ansari X-Prize, for being the first private operation to cross the widely accepted 100km altitude border to space twice within two weeks, in a reusable vehicle capable of carrying three people. SpaceShipTwo and its carrier aircraft are also being built by Scaled, but are much bigger than its originals, to accommodate more passengers.

The two programmes can be seen as a continuous development. Some critics have suggested that despite the large number of early bookings there might not be a long-term business in taking fare-paying passengers on a short ride above the atmosphere. Back in 2009, Scaled Composites boss Burt Rutan was estimating that it would be necessary to build as many as 50 SpaceShipTwos to meet demand for flights, which will be run from a $200 million purpose-built Norman Foster-designed “spaceport” just west of the White Sands missile range in the New Mexico desert, with a 12,000ft runway and paid for by the state, with an eye on tourist revenue.

At Harwell, Whitesides suggested that flights could eventually be run daily, and also noted that flight time was very early in the morning. Thus critics might note that, as the programme stands, 600 passengers translates to at least 100 flights, which at a rate of one a week will stretch out for two years – with revenue of $150 million.

But Virgin Galactic regards the passenger flights programme as merely the beginning of a long commercial journey. Whitesides would not be drawn on the capability of “SpaceShipThree or SpaceShipFour”, stressing that the company’s focus now was to “execute” its suborbital programme.

The LauncherOne programme, however, is clearly another priority. So far, Virgin has indicated that the rocket – which like SpaceShipTwo will be carried to some 50,000ft release altitude by WhiteKnightTwo – will be capable of putting 1m diameter payloads of 225kg (500lb) into low inclination Low Earth Orbit and 100kg to a higher altitude, Sun-sychronous Low Earth Orbit.

Recent launches of multiple shoebox-sized “cubesats” and other miniaturisation efforts support expectations by many space industry players that demand for small satellite launches is poised to expand with the availability of launch vehicles. Thus few would be surprised if Virgin Galactic finds that WhiteKnightTwo makes more flights hoisting LauncherOne units to altitude than passengers.

Either way, there is one characteristic of the Virgin Galactic operation that will surprise no-one. Describing plans for the whole SpaceShipTwo passenger experience, Whitesides got a chuckle with a deadpan remark: “At the end of the day we’ll throw a party for those who are interested, because it’s a Virgin event.”