Reusable launch system

A reusable launch system (RLS) or also Reusable launch vehicle (RLV) is a launch system which is able of launching a payload into space many times and that’s the contrasts of the system of launch now, where each launch of vehicle is launched only one time then discarded. Until now there isn't a completely reusable orbital launch system but if we will use RLV that can provide a lots of benefits such as highly reliable access to space and economic cost advantages . So what is the advantages of the RLV? How can make the future of the system launch better than now?

Probably the simplest way to illustrate the economics of reusable systems is to show how many launches of an RLV are required to amortize investment costs for development, initial inventory, and facilities. The number of launches after amortization represents savings over a comparable expendable system. Since the RLV costs only 10 to 25 percent of the cost for a comparable expendable system (i.e., $2 to $4 million per launch versus $17.5 million per launch), the RLV could perform the missions of smaller, yet more costly, expendable launch vehicles. Such as 35K-lb-payload RLV could be used in place of all vehicles between the Thor and Saturn IB, and thus the 80 launches could be accumulated in a relatively short time, with significant savings in subsequent years.

An added feature of low-cost launch vehicle is its ability to create new uses. That is, as launch costs diminish, it becomes more practical to use space for additional endeavors, giving an added base for investment amortization and thus further increasing the savings per launch. Additionally, an RLV which is designed with growth potential in mind provides a longer operating life span and therefore allows a greater number of years of use after the investment costs have been paid off.

In addition to the economic benefits of recoverable boosters, there are several fringe benefits to be derived. Many recoverable concepts allow a mission abort and recovery of the payload, an especially attractive feature for manned or other particularly high-value payloads. The flight-test program for an RLV is similar to that for an aircraft in that it can be conducted in a stepwise manner with a minimum of test hardware. A vast amount of operating experience and “shakedown” testing can be accumulated before the first payload is launched. Unlike the totally expendable launch vehicles, the RLV can be flight-tested without incurring more than the cost of the expended propellants and the flight-to-flight maintenance.

One of the constraints that has limited the U.S. to only two space bases capable of launching major payloads is the vehicle overflight problem. The U.S. cannot launch rockets over populated areas for fear of debris jettisoned during the normal flight profile or fear of failure. A reusable vehicle with aerodynamic return capability could overcome this problem, since the launch vehicle would be little different from an airliner flying over a city, provided a flight trajectory was chosen so as to minimize ground noise from the propulsion system. An RLV with man aboard could alleviate many of the situations where the launch vehicle has to be destroyed because of minor malfunction. This alleviation of overflight restrictions would allow more launch sites to be developed or take advantage of heretofore unusable facilities, a feature highly desirable for military missions.

Another desirable feature of most RLV concepts would eliminate some of the transportation problems from manufacturing site to launch site. The RLV with aerodynamic qualities would be ferried from the manufacturing site to the launch site and thus eliminate the special carriers in use today, such as Guppies and special booster barges.

The large booster concepts have been mentioned as possible contenders for a considerable portion of future space research money. However, a relatively small RLV could accomplish the missions projected for these large boosters through the assembly-in-orbit concept. While a very large launch system would have very limited application, perhaps less than one launch per year (witness experience with the large Saturn vehicles), a moderately sized RLV could take on the job of the large booster as well as many other smaller missions. An inherent feature of the assembly-in-orbit concept is that a single launch failure does not destroy the entire payload, whereas with the large single-vehicle launch a failure could cause complete destruction of the payload and possibly the whole program. Most of the large-payload concepts already consider some type of resupply and crew rotation capability. An RLV could provide both of these functions in addition to establishing the space station in the first place. A very large booster would certainly require advances in technology and of course new and quite expensive launch facilities, while an RLV could be built with currently available technology and launched from existing facilities usually with only minor modifications.