One Step to LAPAN Satellite Launch Vehicle Realization

July 7, 2009

Source: Kompas Newspaper

RX-420 rocket with diameter 420 mm and length 6.2 m was the biggest rocket that successfully launched into space by Indonesian LAPAN in last 10 years.  With weight 300 kgs, RX-420 flew until 101 kms ground to ground with vertical height 53 kms and speed up to 4.4 machs. This successful launch is a key step to satellite launch vehicle (SLV) that scheduled by LAPAN to be launched in 2014. In that configuration, RX-420 rocket is the main component of LAPAN SLV.



lapan SLV

To transport a satellite in orbital position with height 300 kms, the SLV is designed to be consisted of four-stage propulsion, started with RX-420 (3 units) in the bottommost position as booster, two RX-420 rockets in the second stage and third stage and RX-320 rocket as the latest stage at the top position. This design has length 9,496 mm with total weight is 3.8 tons. One RX-420 rocket weighs around 2 tons with cruise distance 120 kms. With the current SLV configuration, the vertical launch distance may reach 300 kms. This SLV will carry 50 kgs load until the orbital position at height 250 kms. Horizontal speed of the rocket is planned to be around 7-8 kms/sec.

Evaluating the last week launching experiment of RX-420 rocket, LAPAN’s chairman Adi Sadewo Salatun said that LAPAN still requires an improvement or correction particularly at fin, nozzle and propellant components. “The homework has to be finished is to enhance octane value or impulse specific (Isp) from 230 to 300,” he said. For that objective, LAPAN will select finer grain size of ammonium perchlorate (AP) as rocket solid fuel. Currently besides using AP, LAPAN uses aluminum, HTPB (Hidroxy Terminated Polybutadiene) and TDI (Toluena Diisocyanate). As comparison, Chinese uses 9 (nine) combination of material for their SLV solid fuel.

An increased thrust power of the rocket by means of improving Isp can be provided by combining the solid fuel ingredients from four to seven types of material (a combination of solid ingredients, oxidators and additives). For propellant requirement, the factory of AP will increase its production from 2 tons/year to be 10 tons/year.

A correction also will be performed at the nozzle part as ports or conduit of gas exhaust. According to Head of RX-420 Engineering, Lilis Maryani, the nozzles component of that rocket will be reduced its weight about 40% less. Presently, its weight is 90 kgs with graphite block material.

A ratio between structure and propellant weight now is still 50:50. It will be modified to more ideal ratio by reducing the structure weight 200 kgs  less to boost additional rocket speed 3 kms/sec for higher/longer cruise distance. Presently, manufacturing of nozzles were done by milling technique. “To reduce the weight as an improvement, nozzles will be made by casting method through cooperation with state owned steel manufacturer, Krakatau Steel (KS),” Adi added. Cast nozzles will be made from steel and aluminum alloy. Future static test will be performed in December 2009 and next rocket launch test is scheduled in 2010, that is two-stage RX-420 rocket for motor test. The distance (ground to ground) is expected increases from 100 kms to 150 kms. Referring to that configuration, Head of SLV Engineering, Rika Andiarti, said that next year LAPAN will start developing inter-rocket separation system and nozzles at height 20 kms atmosphere condition while second stage motor is ignited.

Adi said,” Another issue is cracked rocket fins problem from the latest experiment due to major influence of localized aerodynamics heating in velocity 4.4 machs or 1.2 kms/sec”. Lilis added,” It will be corrected by adding heat insulator”.

Four-stage configuration of RX-420 and RX-320 which is adopted so far by LAPAN for their SLV still has a disadvantages especially on strap on booster rockets. “If this configuration is not working, we will choose an alternative configuration of combined RX-520 and RX-420 to reduce the structure weight and to increase the rocket speed”, said Adi.

For the rocket payload, Head of LAPAN Payload Engineering, Herma Yudhi Irwanto, said that for future experiment LAPAN will develop vibration dampener for rocket payload, including satellite. In this issue, satellite test engine has been built using LAPAN A1 and A2 satellite technology. The latest info gathered from LAPAN, they will make mobile vehicle as launching truck for other location alternatives, instead of current Pameungpek location, such as in Ujung Kulon-West Java Province and Southern Beach of Bengkulu Province (Sumatera Island). For this year, LAPAN gets additional budget from Rp 30B (US$ 3M) to Rp 50B (US$ 5M) for RX-420 development and RX-520 research.

LAPAN is Planning to Launch RX-420 Rocket on July 02, 2009

June 11, 2009

LAPAN is planning to launch rocket RX-420 for the first time on July 02, 2009. RX-420 is the milestone of the next Indonesian indigenous satellite orbital launching vehicle program.

That  special news was released by Research and Technology Minister Kusmayanto Kadiman, in Jakarta, Thursday, June 11, 2009. Minister in meeting session with Commission VII of Indonesian Parliament said that RX-420 launching with 100 kms distance will be conducted by LAPAN because they had already successfully launched experimental rocket RX-320 in 2008. He added that RX-420 basically has more power than RX-320 and may be boosted up to 190 kms if the rocket structure weight is lighter.

“Its cruise range equivalent to distance between Jakarta to Bandar Lampung”, said Kadiman. The rocket launching plan will be extended in the same year (2010) by launching combined RX-420-420 and in 2011 for combined RX-420-420 – 320 and SOB 420.

In 2014, all experimental rocket launchings should be finished and the rockets must be ready to carry nano satellite with height about 300 kms and speed 7.8 kms/sec. “If we make it happens, it will be monumental achievement as a very special gift from LAPAN to the country”, said Kadiman again.

Meanwhile, LAPAN Chairman, Adi Sadewo, also informed that LAPAN previously has done trial on two-stage rocket launching RX-150-120 supported by TNI-AD (Indonesian Army) and PT Pindad. Rocket with cruise distance 24 kms has successfully been launched from moving vehicle (Pindad Panser) on March 31, 2009 –> VERY GOOD NEWS!!!


LAPAN also has performed rocket launching trial of RX-D230 (RX-122) with cruise distance 14 kms that can be released from tube launcher on May 05, 2009. That rocket has main function to know the field condition prior to deploying marine soldier to the beach.

Another report gathered today, LAPAN also working with several institutions for flash arrester rocket project to protect important facility and working for artificial rain maker rocket project.

Taken from Kompas, Thursday, June 11, 2009 , kaskus

LAPAN and Indonesian Rocket Program

May 24, 2009

LAPAN or Lembaga Antariksa dan Penerbangan Nasional (English: National Institute of Aeronautics and Space) is the government space agency. it was established on november 27, 1964 by President Suharto. Its function similar to NASA that responsible for long term civilian and military aerospace research.

For several years, there was no big news from LAPAN that incorporated with their program since their rocket launching test performed in 1962 with “Kartika” as the rocket code name. The different story is being delivered by LAPAN at this moment. After their collaboration with Germany institute (TU of Berlin) to develop micro satellite up to its service now (called LAPAN-TUBSAT satellite; launched in 2007), they started growing the intensity of the program, in developing new Indonesian built satellites and rocket testings prior to launching program that scheduled in 2014.


Proving their capability and independence, LAPAN now finishing LAPAN-A2 as improved LAPAN-TUBSAT and Communication Repeater Satellite for Indonesian Amateur Radio Association in Bogor, West Java.





The launching to the orbital of those satellites  are planned using Indian rocket in 2009 and 2010 with piggy back method. Especially for the  LAPAN-A2, it has additional improvements by adding some components results in heavier load with 65 kgs than 57 kgs LAPAN-TUBSAT, designed to have long distance remote sensing or surveying with resolution 5 and 200 meters, GPS transmitter for satellite position and time, altitude determination and control system (AD-CS) for body controlling system and stability especially during data acquisition, data storage and automatic camera control to reach specific geographic area. The size of LAPAN-A2 is 60 cm x 60 cm x 80 cm.


A variety of satellite application and increasing demand of this media, worsened by embargo/veto for Indonesia not to purchase any kind of rocket components, drive Indonesia to empower all internal capability and resources independently building and developing rocket as orbital satellite launcher.

LAPAN that already 45 years on November 27, since 2007 had boosted rocket and satellite study and development, especially after got ability to produce solid rocket fuel.

In 2007, RX-250 (250 mm) had been launched successfully with distance 53 kms. After good result on static test, RX-320 rocket has successfully launched in Pameungpek, West Java on May 19, 2008 by transmitting navigation system data, aerodynamics performance, trajectory, environment condition and any obstruction during  launching. The special improvement from this test was RX-320 rocket used Indonesian own solid propellant. RX-320 rocket has dimension 320 mm diameter x 4,736 mm long and weight 532 kgs. The trust power is 52 ton/sec and reached 42 kms as per design.

roket-prmi-lapan-di-pandansimo RX-100


Rx-320 lapan

RX-250 lapan b




roket lapan rx-320

summaryphoto rx-320

After successfully launched that experimental rocket with diameter 320 mm or coded RX-320 (the biggest so far for Indonesian built rocket), LAPAN again succeeded static test RX-420 on Tuesday (23/12/2008) at LAPAN Aerospace Technology Center, Tarogong, Tangerang. In 2009, Chief of LAPAN Adi Sadewo Salatun said after successful static test of RX-420, rocket launching program will be continued in 2009.

Testing of experimental rocket with diameter 420 mm (RX-420) has been postponed for a week because still required additional ballast load at propulsion tail for safety reason. In firing condition, this rocket may have 10 tons in 11 sec. From the test, the performance is slightly better than design, especially on boosting power. Its launching schedule is rumored will be sometime in July 2009 after the first stage of Indonesian president election.

This RX-420 rocket is the main part of the first LAPAN satellite orbital launching vehicle (SLV-1) that scheduled in 2014, said by Yus Kadarusman Markis, chief of LAPAN Aerospace Technology Center. SLV-I consists of three-stage rockets, which is in the first stage will be three RX-420 as booster, in second stage one RX-420 as sustainer and the last is three RX-320. With that configuration and LAPAN solid fuel, the SLV-1 has capability to launch nano satellite to the orbit.

SLV Lapan

One RX-420 rocket weighs up to 2 tons is designed to have distance range about 120 kms,. With SLV-1 configuration, it may reach a vertical height up to 400 kms. This rocket can be loaded 50 kgs load to be able to the orbit minimum 250 kms high and at horizontal speed at 8 kms/sec.


For the next development, LAPAN will develop rockets with bigger diameter, such as RX-540 dan RX-750 and liquid fuel that has better performance than solid fuel. RX-420 is the sixth rocket developed by Lapan after 70, 100, 150, 250, and 320 mm.

solid_n_liquid_propellant NASA

As the limited budget as the major problem (as usual for Indonesia) for funding the research and experimental work, LAPAN still has many agendas in their work. One of that is there is a plan to modify the function of this developed rocket for military use to be balistic missile as a part of state independence on domestic built main strategic armament. However, LAPAN is not involved on that policy and it solely government decision (c.q. defense ministry and etc).

Taken from several sources (LAPAN, Kompas, etc).