IRNSS-1H – PSLV-C39 (XL) – Шрихарикота – 31.08.2017

[tnt22]

http://www.isro.gov.in/update/31-aug-2017/pslv-c39-flight-carrying-irnss-1h-navigation-satellite-unsuccessful

Aug 31, 2017

PSLV-C39 Flight Carrying IRNSS-1H Navigation Satellite Unsuccessful

The forty first flight of India's Polar Satellite Launch Vehicle (PSLV-C39), conducted today (August 31, 2017) evening from Satish Dhawan Space Centre SHAR, Sriharikota, was unsuccessful. PSLV-C39 had a normal lift-off at 1900 hrs IST (7:00 pm) and all the flight events took place exactly as planned, except heat shield separation. This resulted in satellite separation occurring within the heat shield. The satellite is inside the heat shield resulting in the unsuccessful mission. Detailed analysis is under progress to identify the cause of the anomaly in the heat shield separation event.

[tnt22]

Выступление председателя ISRO К.Кумара на пресс-конференции после пуска

BREAKING NEWS | IRNSS-1H mission from Sriharikota was unsuccessful, says ISRO chairman | Press Meet

Thanthi TV

Опубликовано: 31 авг. 2017 г.

(3:36)

[tnt22]

http://www.ndtv.com/india-news/indias-first-private-sector-built-satellite-launched-by-isro-from-sriharikota-1744575

India's First Private Sector-Built Satellite Launch Unsuccessful, Says ISRO: 10 Facts

"The 41st mission of PSLV has been unsuccessful. The heat shield did not separate and the satellite remains enclosed within the heat shield," said ISRO chairman AS Kiran Kumar. The trouble began three minutes into the launch but the outcome was known only 19 minutes later. The failure is of the rocket and the satellite built by the private consortium remains untested, scientists said.
...

[tnt22]

http://spaceflight101.com/pslv-c39/pslv-launch-failure-irnss-h/

Two-Decade Success Streak Ends with PSLV Launch Failure on IRNSS-1H Mission
August 31, 2017


File Image of India's PSLV Rocket taking off at Night – Photo: ISRO

A streak of 36 successful launches over a period of 18 years ended on Thursday when India's PSLV rocket suffered an in-flight failure that left its payload – a replacement satellite for the Indian Regional Navigation Satellite System – in a lower- than-planned orbit and possibly trapped underneath the rocket's payload fairing.

According to the Indian Space Research Organization, the fate of the PSLV was sealed three and a half minutes into its planned 19.5-minute mission when the protective payload fairing failed to separate from the ascending rocket. Dragging the dead weight of the fairing, the rocket did not have the energy needed to attain its planned orbit peaking 20,650 Kilometers in altitude and only reached a much lower orbit of 167 by 6,555 Kilometers.

Спойлер

An open question is whether the payload fairing remained intact around the IRNSS-1H satellite after it separated from the rocket's upper stage – creating a potentially dangerous configuration with a fully-fueled satellite bouncing around within the fairing. Tracking data expected later on Thursday will clarify if the fairing remained in place around the fourth stage.


PSLV C39 Pre-Launch – Photo: Indian Space Research Organization

Thursday's launch marked the 41st flight carried out by the Polar Satellite Launch Vehicle that has become the undisputed workhorse of the Indian space program – supporting the country's Earth observation programs, sending up communications satellites and dispatching probes to the Moon and Mars, also becoming a player on the commercial launch market as a cost-effective alternative for small satellite operators. It marked the third failure encountered by PSLV following a mishap on its very first mission in 1993 and a partial failure on its first operational flight in 1997 that left the payload in a lower-than-planned orbit.

PSLV had raked up 36 consecutive successes since its C2 mission in 1999 and, in recent years, stepped up its launch pace to become a dependable workhorse, not only for India, but a number of international customers that placed satellites on the four-stage rocket.

Thursday's flight started with an on-time liftoff at 7 p.m. local time, 13:30 UTC from the Second Launch Pad at the Satish Dhawan Space Center on India's East Coast. Blasting off half an hour after sunset, PSLV raced into the night under the loud thunder of its massive solid-fueled core stage and four ground-lit boosters, catapulting the vehicle off its pad with a thrust of 700 metric-ton-force.

Powering away from the Indian coast toward the south east, PSLV ignited the two remaining boosters when passing 25 seconds into the mission to increase the vehicle's thrust to over 800 metric ton-force. The 44.4-meter tall rocket shed the four ground-lits at T+70 seconds followed by the twin air-lit boosters one minute and 32 seconds into the mission while the first stage continued to burn until T+110 seconds.


Actual Flight Events Timeline based on PSLV Telemetry (Fairing Separation not listed) – Image: ISRO / DD News

With the 20-meter long core stage dropping away, PSLV fired up the liquid-fueled Vikas 4 engine on the second stage, pushing the vehicle out of the atmosphere with a thrust of 81,500 Kilogram-force. Three minutes and 24 seconds into the mission, PSLV had reached an altitude of 115 Kilometers, making it safe to jettison the payload fairing that enshrouds the delicate satellite during atmospheric flight to protect it from aerodynamic forces which would easily rip it apart.

Fairing separation is completed as early as safely possible to shed no-longer-needed mass and thus increase the rocket's performance, having to push less weight into orbit. However, in Thursday's case, no verbal confirmation of fairing separation was provided in real time and telemetry displays showing flight event times based on sensor data from the rocket did not register the fairing separation.

The second stage handed over to the solid-fueled third stage four minutes and 24 seconds into the flight, firing up its rocket motor on a 112-second burn to accelerate the vehicle onto a sub-orbital arc. Plots displaying the rocket's velocity vs. time and altitude vs. time as it progressed toward orbit began showing a considerable underperformance as the third stage was burning – a result of the rocket carrying the additional 1,150 Kilograms of fairing mass that were not planned to be present at this stage of the flight.


Trajectory Displays shows a significant underperformance suffered by PSLV C39 – Image: ISRO / DD News

The third stage managed to accelerate the vehicle to a speed of 6.96 Kilometers per second whereas the planned PS3 cutoff speed was 7.28km/s, representing a shortfall of 320 meters per second. In an attempt to rectify the situation, PSLV's computers calculated a new flight profile for the fourth stage, firing up its twin L-2-5 engines eight minutes and 50 seconds into the flight, around one and a half minutes earlier than planned. The fourth stage was up and running for eight minutes and 48 seconds, consuming all available propellants in an effort to stretch the rocket's available energy.

Data displays showed PSLV achieved an orbit of 167.4 by 6,554.8 Kilometers, inclined 19.18 degrees – well short of the target 284 x 20,650-Kilometer orbit. Spacecraft separation was commanded 17 minutes and 56 seconds into the flight at which point loaded springs were to push the IRNSS-1H satellite away from the rocket's fourth stage.


A Launch Controller looks at onboard video from PSLV showing the Fairing still in place around the satellite – Photo: ISRO / DD News

What transpired at this point is uncertain – one scenario could be that the satellite separated and ended up bouncing around within the closed fairing, but there are also possibilities of the fairing giving way. The satellite was likely programmed to extend its power-generating solar arrays after a defined period of time following separation which could be another potentially harmful event with the fairing still in position. Tracking data expected later on Thursday will confirm whether the PS4-IRNSS-Fairing stack remained intact or whether debris are present.

Thursday's PSLV mission carried IRNSS-1H – the eighth satellite to launch as part of the Indian Regional Navigation Satellite System (IRNSS) and one of two ground spares built for the operational seven-satellite constellation called into service after clock failures on the IRNSS-1A satellite left the orbiting constellation without redundancy.


Photo: ISRO

Initiated in 2006, the IRNSS project has the overall goal of establishing an independent navigation capability across India for government and civilian use, ending reliance on outside programs such as GPS which may be disabled in times of distress. Opting for a regional solution, India deployed seven IRNSS satellites between 2013 and 2016, three residing in Geostationary Orbit above the equator and four orbit in inclined Geosynchronous Orbits using two orbital planes to create a coverage area across the entire Indian territory and around 1,500 Kilometers beyond its borders.

The satellites are nearly identical, based on the Indian Space Research Organization's I-1K platform, each weighing in at around 1,425 Kilograms and hosting three rubidium atomic clocks that deliver the ultra-precise timing needed for the generation of navigation signals which are then transmitted to the ground in the L5 band and processed by compatible receivers to calculate a user's position via triangulation – requiring a sufficient number of satellites, typically four, to be visible at any given time.

IRNSS was designed with redundancy on the constellation and satellite levels – installing three clocks on each satellite to protect against isolated failures and operating the constellation in a one-redundant configuration. Additional insurance against a system outage came in the form of two ground spares, intended to be sent up in case any of the active satellites encountered problems to guarantee the first IRNSS generation can meet its planned ten-year life time.


IRNSS Constellation – Image: ISRO

The problems aboard IRNSS-1A began in mid-2016 with the failure of one of its three atomic clocks with the other two following suit over the course of the second half of the year. This left the satellite severely disabled in its ability to deliver accurate navigation data. IRNSS-1A is still providing systems messages and coarse navigation signals but is not useful in precision applications.

The plot thickened in 2016 when the European Galileo constellation also noted an alarming failure rate on its clocks, affecting both types used on the European system – the more accurate Hydrogen Masers and the Rubidium Atomic Standard Clocks which are considered more robust. IRNSS, Galileo and China's Beidou-2 navigation systems all use clocks from the same supplier, Swiss company Spectratime, and analysis of the failures on IRNSS and Galileo showed the exact same mechanism that implicated an inexpensive electronics component causing short circuits within the clocks.


Photo: ISRO

The early Galileo In-Orbit Validation Satellites and the Beidou-2 system were not affected by the clock troubles as an earlier production series at Spectratime did not feature the component in question.

As a result of the inquiry into the clock troubles, existing clocks were removed from the two IRNSS spares and Galileo satellites waiting for launch to undergo repairs before being re-installed on their respective satellites. However, for the satellites already in orbit, there is no fix for the systemic clock issue – leaving 18 Galileo satellites and seven first generation IRNSS satellites at risk of complete rubidium clock failure.

To extend the operational lives of the satellites in orbit, ISRO decided to change the procedure of how the three clocks are operated. Initially, two clocks were kept in a powered state with one in primary mode and the other as a hot backup while the third was powered down. As a life extension measure, IRNSS satellites now only have one clock in a powered state, keeping the other powered off to preserve their useful lifetime for when they are needed.

To keep the constellation in a fully operational configuration, ISRO elected to call up the two ground spares for launch in 2017. IRNSS-1H was to maneuver into a 29-degree inclined Geosynchronous Orbit at 55 degrees East to replace the IRNSS-1A satellite launched in July 2013. This role will now be filled by the IRNSS-1I satellite that had been preparing for a November liftoff on a PSLV to join the constellation as additional backup in case of future clock troubles.

[свернуть]

[tnt22]

НОРАД зафиксировал один объект запуска
 

[tnt22]

Spaceflight101‏ @Spaceflight101 2 ч. назад

#PSLV Stage 4/IRNSS-1H Satellite/Payload Fairing cataloged as 2017-051A in a 166 by 6,556-Kilometer orbit, inclined 19.16°.

[zandr]

http://tass.ru/kosmos/4522463

Индийский навигационный спутник вышел из строя при запуске
НЬЮ-ДЕЛИ, 31 августа. /ТАСС/. Отказ системы защиты от перегрева привел к гибели индийского навигационного спутника 1Н, выведенного в четверг на орбиту ракетой- носителем PSLV. Об этом сообщил глава Индийской организации космических исследований (ISRO) Киран Кумар.
"У нас произошла проблема, мы пытаемся разобраться в ситуации, проводится детальный анализ", - заявил он, признав, что, несмотря на успешный вывод навигационного спутника-дублера на заданную орбиту, миссия провалилась.
"Спутник находится на заданной орбите, но тепловая оболочка, предохраняющая аппарат от перегрева во время полета, не раскрылась", - уточнил Кумар.
Ранее Индийская организация космических исследований известила об успешном 41-ом запуске ракеты PSLV, произведенном в 19:02 (16:32 мск) с космодрома на острове Шрихарикота в Бенгальском заливе.

Спойлер

По замыслу индийских ученых, 1Н массой 1425 кг должен был подменить первый из семи уже работающих на орбите спутников навигационной системы - 1А, у которого вышли из строя трое рубидиевых атомных часов. Аналогичная проблема с атомными часами произошла недавно у европейской системы Galileo - сбои случились на половине спутников европейского созвездия.
Для постройки и тестирования 1H ISRO впервые привлекла консорциум из шести малых и средних частных индийских предприятий.

[свернуть]

[Pirat5]

31.08.2017 

Запуск индийского навигационного спутника признан неудачным
... Запуск признан неудачным – не произошел сброс головного обтекателя. Хотя космический аппарат и удалось вывести на околоземную орбиту с параметрами 19,16 град. х 166 х 6556 км, использовать его по назначению не представляется возможным.

А.Ж.

особенности перевода...

zandr пишет:
"Спутник находится на заданной орбите, но тепловая оболочка, предохраняющая аппарат от перегрева во время полета, не раскрылась", - уточнил Кумар.

[tnt22]

http://indianexpress.com/article/technology/science/isro-suspects-pyro-elements-failed-to-separate-rockets-heat-shield-4831240/

ISRO suspects pyro elements failed to separate rocket's heat shield

As a result of the heat shield not separating the 1,425 kg navigation satellite IRNSS-1H got stuck inside it resulting in the failure of the around Rs 250 crore mission.

By: IANS | Published:September 6, 2017 2:56 pm


According to K. Sivan, Director, Vikram Sarabhai Space Centre (VSSC), all the systems during the rocket's flight worked well while the only suspect place is the pyro elements. (Image Source: PTI)

The Indian space agency is strongly suspecting the failure of pyro elements for the non-separation of the heat shield of its rocket Polar Satellite Launch Vehicle's (PSLV) XL variant on Aug 31, said a senior official. As a result of the heat shield not separating the 1,425 kg navigation satellite IRNSS-1H got stuck inside it resulting in the failure of the around Rs 250 crore mission.

Спойлер

Normally the heat shield will be separated soon after the rocket crosses the earth's atmosphere. According to K. Sivan, Director, Vikram Sarabhai Space Centre (VSSC), all the systems during the rocket's flight worked well while the only suspect place is the pyro elements.

The VSSC is part of the Indian Space Research Organisation (ISRO). "Tests are going on to find out the reasons for the failure of heat shield separation. Each test takes around 72 hours," Sivan told IANS.

One fortunate aspect of the failure is that ISRO has all the flight data as the rocket was not lost during its one way journey. Sivan said the heat shield would separate after on-board computers give the command to ignite the explosives. The explosives would then ignite and explode to separate the two parts of the heat shield joined by bolts.

[свернуть]

[che wi]

The Indian Space Research Organisation expects to resume launch of satellites in a couple of months once its failure analysis committee releases its report. The committee is conducting tests on why the PSLV-C39 mission of August 31 failed to release a back-up navigation satellite into space.

ISRO Chairman A.S. Kiran Kumar on Friday said the committee would release its report "very soon".

Спойлер

The launches would be resumed in November or December after necessary steps are taken. He was speaking on the sidelines of an event to mark 25 years of the formation of Antrix Corporation, which markets ISRO's products and services.

On the loss of IRNSS-1H in the launch, Mr. Kiran Kumar said the existing fleet of six spacecraft met all required specifications and there was no urgency for a replacement. "The overall performance of the [navigation] system is not affected," he said.

[свернуть]

http://www.thehindu.com/sci-tech/science/isro-to-be-back-with-launches-in-nov-dec/article19693943.ece

[tnt22]

http://www.thehindu.com/todays-paper/tp-national/pyro-devices-to-blame-for-pslv-failure-isro/article19738850.ece

Pyro devices to blame for PSLV failure: ISRO
 
Special Correspondent

Thiruvananthapuram, September 23, 2017 00:00 IST
Upd ated: September 23, 2017 04:57 IST

The Indian Space Research Organisation (ISRO) has come round to the inference that the PSLV C-39 mission on August 31 was doomed by the failure of the pyro devices that actuate the separation of the heat shield encasing the satellite from the rocket.

Спойлер

A high-level meeting chaired by ISRO chairman A.S.Kiran Kumar held at the VSSC here on Friday came to the conclusion on the failure of the pyro devices. The meeting was informed that simulation exercises were on to ascertain the reason for the malfunctioning of the pyro devices.

'Component isolated'

"We have isolated the component responsible for the failure of the mission but it remains to be established why it failed to function," VSSC Director Dr. K.Sivan said. "We are testing various versions and hope to arrive at a consensus in seven to 10 days". The exercises are expected to help the scientists analyse the failure from various angles.

ISRO had declared the PSLV- C39 mission unsuccessful after the heat shield refused to open and release the IRNSS-1H navigation satellite on board. The failure review committee se t up by ISRO had zeroed in on the electrically-operated pyro devices as the culprit after it was found that the command for separation had gone through but failed to trigger the mechanical process that pops open the heat shield.

Pyro devices use small charges to actuate the release mechanism that forces the fairings apart.

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[tnt22]

https://timesofindia.indiatimes.com/home/science/isro-to-launch-cartosat-2-sat-with-30-nano-sats-in-mid-december/articleshow/61176190.cms

Isro to launch Cartosat 2 sat with 30 nano sats in mid-December

Surendra Singh | TNN | Updated: Oct 23, 2017, 05:26 IST

...
Dr Sivan said, "After the IRNSS-1H satellite failure, corrective measures will be taken in all rockets before the launches." Though the inquiry into reasons for the heat shield glitch is still going on, "initial findings suggested a defect in the pyro elements of the rocket which deal with the stage separation mechanism". The VSSC director said the committee probing the failure of IRNSS-1H launch will submit its investigation report much before the upcoming launches.

He said the faulty satellite stuck inside the heat shield is still orbiting the outer space and is "unlikely to fall into the Pacific Ocean anytime soon". On August 31, PSLV-C39 could not deliver the 1.4-tonne IRNSS-1H in the geo orbit as its heat shield did not get separated minutes after the rocket's lift-off from Sriharikota.

[tnt22]

https://timesofindia.indiatimes.com/india/make-in-india-isro-private-firms-joint-venture-to-launch-rocket-by-2020/articleshow/61341690.cms

Make in India: Joint venture of Isro and private firms to launch rocket by 2020
Chethan Kumar | TNN | Updated: Oct 30, 2017, 19:22 IST

...
Inadequate pressure failed heat-shield separation

Isro chairman AS Kiran Kumar on Monday said that inadequate pressure in the bellow pump resulted in the heat shield not separating from the satellite, resulting in a failure of the mission on August 31.

The PSLV C-39 was carrying the IRNSS-1H was then declared an unsuccessful mission. The committee looking into the failure analysis, Kumar said, has found that the automated commands were performed accurately.

"There was no fundamental problem, that's clear. A system that has performed so well on so many occasion could not just go wrong. The failure happened because there was not enough pressure in the bellow pump, which resulted in the non-separation," Kumar said.

He said that a lot of external variables were responsible for this and the final report of the committee is awaited. Another senior official from Isro said that the simulations and other analysis by the committee is complete and that the report will soon be out.

[Старый]

tnt22 пишет:
The failure happened because there was not enough pressure in the bellow pump , which resulted in the non-separation," Kumar said.

Ничего не понял. Перевёл гуглопереводчиком. Опять ничего не понял. Какое такое недостаточное давление? В каком таком нижнем насосе?   Они чем вобще обтекатель сбрасывают? 

[che wi]

Старый пишет:

В каком таком нижнем насосе?

Там же не "below" pump, а "bellow" pump.

Здесь есть небольшое описание сброса обтекателя:

The fairing is separated at an altitude of 115 Kilometers. Separation is accomplished by a linear piston cylinder separation and jettisoning mechanism (zip cord) running along the full length of the PLF and a clamp and joint at the base of the fairing. Both systems are pyrotechnically initiated. The gas pressure generated by the zip cord expands a rubber bellow that pushes that piston and cylinder apart, pushing the fairing halves laterally away from the launcher.

[Старый]

che wi пишет: 
Там же не "below" pump, а "bellow" pump.

Я и словов то таких не знаю... Гуглпереводчик говорит что "bellow" это "рёв, мычание".

[Старый]

Там же не "below" pump, а "bellow" pump.

Тогда уж наверно сразу "bellows"?
Меха, сильфон. Это оно? А что за насос?  :oops:
Вобщем получается что какието меха не надулись и створки не растолкнулись?

[tnt22]

https://timesofindia.indiatimes.com/home/science/isro-to-launch-31-satellites-in-december/articleshow/61691451.cms

Isro cautious about December satellite launch
Nov 17, 2017, 06.44 PM IST

THIRUVANANTHAPURAM: After the recent failure of PSLV-C39 on August 31 this year, Isro centres here including VSSC and LPSC are doubly cautious. They are focused on the next mission of PSLV-C40 to launch 31 satellites including Cartosat -2ER by December end this year.
...

In the previous PSLV launch, there was no design fault. The heat-shield at the top nozzle of the rocket failed to release the satellite into orbit and it could be due to a fault in pyro-techniques, he said.

Normally the heat shield split into two halves at the conical nozzle opens up to release the satellite into the orbit, it failed to open 20 minutes after lift-off, the scientist explained. The heat shield is designed to absorb excessive heat produced by friction against atmosphere during take-off and to protect the components and fuel tanks of the rocket.

"The reason why it failed could be due to some hitch in the pyrotechnic material of the heat shield or probably failure of the springs to trigger the force against atmosphere to open the shield to eject the satellite out. The exact reasons are being ascertained by the 'Failure Analysis Committee of core scientists and the report will be released soon, said a lead scientist at VSSC.

...

While a VSSC scientist said, the failure analysis report is ready but it will be released only within the Isro centres. Based on its findings and recommendations all precautions will be taken to avert any failure, we are doubly cautious. A series of tests will be conducted before the next mission of PSLV-C40 slated for Dec end, he said.

...

[tnt22]

Вышел документ - FAILURE OF PSLV C-39 MISSION - ответы на парламентских слушаниях (192.4 KB, 2017-12-21 07:09:44 UTC)

[tnt22]

NewSpace India‏ @NewSpaceIndia 6 мин. назад

Decay rate of IRNSS-1H/PS4 stack. http://dlvr.it/QLWfKx