Press Release


  This press release is issued by NASDA.

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Results of the Cryogenic Test for H-IIA Launch Vehicle No.4

November 28, 2002 (JST)

National Space Development Agency of Ja

The National Space Development Agency of Japan (NASDA) conducted the cryogenic test for H-IIA Launch Vehicle No.4 (H-IIA/F4) at Tanegashima Space Center on 28 November 2002 and got successful results.

The cryogenic test was to verify the functions of the Launch Vehicle and the Ground Facilities by loading liquid fuel with the same procedures as these on the launch day.

NASDA would like to express its deep appreciation for the valuable cooperation extended by the people and related organizations to the cryogenic test of H-IIA/F4.


Quick Review Results of H-IIA Launch Vehicle No.4 Cryogenic Test

No.ItemReview ItemReview Result
1 Confirmation of the launch vehicle and ground equipment integrity during cryogenic propellant loading. Confirm that there is no anomaly in the data and the functionalities listed below.
  1. Automatic loading function.
  2. Normal temperature / Cryogenic helium pressure bottle high pressure leakage test.
  3. Valve operations under the cryogenic condition.
  4. Automatic count down sequence.
    (Confirmation of the sequence up to the moment equivalent to the first stage engine ignition, as well as the automatic emergency shutdown items)
 The major functions and data listed below were found good, and the cryogenic test fulfilled its purpose.
  1. Automatic loading function
    Confirmed that the loading can be well accomplished.
  2. Normal temperature / Cryogenic helium pressure bottle high pressure leakage test.
    Pressure loss data of pressure bottle was confirmed smaller than the specified values.
  3. Valve operation under the cryogenic condition.
    Valve operations were found good.
  4. Automatic countdown sequence
    The automatic countdown sequence proceeded nominally and the emergency shutdown occurred as planned at the moment equivalent to first stage ignition.

Note:
Up to 1 MPa of reverse pressure was exerted on the first stage Liquid Oxygen Fill and Drain Valve (OFDV) when the loading was stopped during the liquid oxygen loading.
Cryogenic test was resumed, after preventive actions were taken and the OFDV was checked for integrity.

2 The radio link to the launch facility systems. Check the radio link of telemeters, radars, and commands. Confirmed that the radio link between launch vehicle and the launch facility systems were found good.



First Stage LOX Fill and Drain Valve (OFDV) Negative Pressure Malfunction (Reference)

Malfunction:
When the LOX loading sequence was stopped manually (nominal procedure), OFDV had to be closed after the fill valve closure. However, OFDV closed before the fill valve did. As a result, 1.05 MPa of reverse pressure was exerted on the OFDV.


Cause:
Steps to detect the fill valve closure was simplified for Flight No.4. However, because of the delay time it takes to close the fill valve, OFDV closed before fill valve did.


Action:
* The condition of detection was changed back to be equivalent of the flight No.3.
* Cryogenic test was resumed after OFDV was checked and confirmed that there was no leak.
* The X-0 mark was changed to 2 p.m. to investigate and deal with the problem stated above (4 hours delay).