Friday, July 9, 2010

GSLV-D3 Failure Analysis Report

The GSLV-D3 Failure Analysis Report is out. Posting the report in full:

The third developmental flight of Geosynchronous Satellite Launch Vehicle (GSLV-D3) conducted on April 15, 2010 from Satish Dhawan Space Centre SHAR, Sriharikota, primarily for the flight testing of indigenously developed Cryogenic Upper Stage (CUS), could not accomplish the mission objectives. Consequently, ISRO had instituted a two-tier process to carry out an in-depth analysis of the flight performance, identify the causes of failure and recommend corrective measures.

The Failure Analysis Committee comprising multi-disciplinary experts completed the analysis and its findings were further reviewed by a National Group of Eminent Experts. These reviews have brought out that:

  1. Following a smooth countdown, the lift-off took place at 1627 hrs (IST) as planned. All four liquid strap-on stages (L40), solid core stage (S139), liquid second stage (GS2) functioned normally.

  2. The vehicle performance was normal up to the burn-out of GS-2, that is, 293 seconds from lift-off. Altitude, velocity, flight path angle and acceleration profile closely followed the pre-flight predictions. All onboard real time decision-based events were as expected and as per pre-flight simulations.

  3. The navigation, guidance and control systems using indigenous onboard computer Vikram 1601 as well as the advanced telemetry system functioned flawlessly. The composite payload fairing of 4 metre diameter inducted first time in this flight, also performed as expected. Performance of all other systems like engine gimbal control systems and stage auxiliary systems was normal.

  4. The initial conditions required for the start of the indigenous Cryogenic Upper Stage (CUS) were attained as expected and the CUS start sequence got initiated as planned at 294.06 seconds from lift-off.

  5. Ignition of the CUS Main Engine and two Steering Engines have been confirmed as normal, as observed from the vehicle acceleration and different parameters of CUS measured during the flight. Vehicle acceleration was comparable with that of earlier GSLV flights up to 2.2 seconds from start of CUS. However, the thrust build up did not progress as expected due to non-availability of liquid hydrogen (LH2) supply to the thrust chamber of the Main Engine.

  6. The above failure is attributed to the anomalous stopping of Fuel Booster Turbo Pump (FBTP). The start-up of FBTP was normal. It reached a maximum speed of 34,800 rpm and continued to function as predicted after the start of CUS. However, the speed of FBTP started dipping after 0.9 seconds and it stopped within the next 0.6 seconds.

  7. Two plausible scenarios have been identified for the failure of FBTP, namely, (a) gripping at one of the seal location and seizure of rotor and (b) rupture of turbine casing caused probably due to excessive pressure rise and thermal stresses. A series of confirmatory ground tests are planned.

After incorporating necessary corrective measures, the flight testing of Indigenous Cryogenic Upper Stage on GSLV is targeted within a year.

In the meantime, the next two GSLVs would fly with the available Russian Cryogenic Stages.

Thursday, July 8, 2010

PICTURES: Indian Space Transportation System - Present Scenario and Future Directions

The presentation titled 'Indian Space Transportation System - Present Scenarion and Future Directions' presented by Dr. B.N.Suresh on 19th June, 2009 at TIFR, Mumbai. Credit:ISRO Click on the slideshow for larger images.

Important Observations:
  • Slide 20 gives us an idea of the Indian interplanetary missions on the drawing board. The slide also gives the orbital and fly-by payload capacities of PSLV, GSLV and GSLV -Mk III to Mars, Venus and Asteroid (very vague definition in this case) respectively. The approximate date for robotic missions to Venus and asteroids is mentioned in Slide 34 as 2018 (Interplanetary missions beyond Mars). The Martian mission according to ISRO will take place only after 2015.
  • Slide 20 mentions the performance specifications of GSLV-Mk III i.e 4.5 tons to GTO and 10 tons to 400 km LEO. In addition it clearly specifies the growth potential to as 5 to 6 tons to GTO, a previously speculated figure. Slide 14 illustrates the flight sequence of Mk III.
  • Slide 25-Slide 28 gives some information of the RLV program. Slide 25 is the image of RLV-TD. Slide 26 shows the RLV with an air-breathing engine. Slides 27 and 28 shows the configuration and flight profile of an RLV-TSTO (Two Stage to Orbit) version.
  • Slides 29-33 has information regarding the Indian Human Spaceflight Programme. The slides give information about the crew vehicle and the human-rated GSLV that would launch it and the mission profile. Slide 33 has already been discussed in detail in an earlier post.

Sunday, July 4, 2010

ISRO Heavy Lift Vehicle

A slide for Dr. B N Suresh's presentation titled 'Indian Space Transportation System: Present Scenario and Future Directions' at TIFR-Mumbai, 19th June 2009 Credit:ISRO

In an earlier post Super Nova had reported on the preliminary concept of an Indian Lunar manned mission presented at IAC-2009. That concept envisaged the development of a crew launch vehicle and a Cargo Launch Vehicle with payload capabilities of 31 and 84 tons respectively to Low Earth Orbit.

The above image shows another concept Heavy Lift Vehicle (HLV) which would be able to haul 100 tons to LEO. What is interesting in this architecture is that no solid stages would be used on the vehicle. 4 SC460 Semi-cryogenic boosters with the SC800 first stage would generate the lift-off thrust for the vehicle. The C100 upper stage would probably serve as an Earth Departure stage (EDS) .

In addition to the HLV, the presentation slide also gives us an idea of the role that the GSLV-Mk III would play in lead up to Lunar manned mission and more importantly in the Indian Human Spaceflight Program.

As we know the present Human Spaceflight concept envisages the development of a crew capsule (Orbital Vehicle) which would be launched by the GSLV-Mk II. This capsule would probably not feature any docking system due to restriction in the payload capacity of GSLV-Mk II (around 5 tons).

Given the greater capability of Mk-III, ISRO plans to use the vehicle to launch a bigger, better equipped crew capsule which would be use to demonstrate rendezvous and docking in addition Extra Vehicular Activity (EVA).