third stage engine anomaly, more likely burnout and explosion with LOX tank rupture can be seen in this video
If both lines were lowering its pressure, it seems very unlikely that it was a pipe blockage problem.
Quote from: baldusi on 12/26/2011 06:21 pmIf both lines were lowering its pressure, it seems very unlikely that it was a pipe blockage problem. in theory1. malfunction of helium pressurization system -> low inlet pressure -> bad working lower bound mode -> more chances for cavitations and instabilities -> ? ->thrust drop -> emergency shutdown.2. pressure drop in Ker line before injector head of chamber -> leak ->? ->thrust drop -> emergency shutdown.
Quote from: B. Hendrickx on 12/25/2011 08:44 amSpectacular footage of the Meridian launch as seen from the cockpit of a Russian airplane :This appears to show the shutdown of the third stage engine (about 1m25s into the clip). If so, the stage looks rock stable until the shutdown (no spinning, etc.).An interesting view of the launch. It looks to be directly downrange on the flight azimuth! - Ed Kyle
Spectacular footage of the Meridian launch as seen from the cockpit of a Russian airplane :This appears to show the shutdown of the third stage engine (about 1m25s into the clip).
With the successful launch of a Soyuz 2-1a, the pressure on ISS has been relaxed a bit.
Quote from: Danderman on 12/28/2011 05:35 pmWith the successful launch of a Soyuz 2-1a, the pressure on ISS has been relaxed a bit.I disagree. It is a systemic problem. You have the Russians saying what they said about their workforce and their processes. The fact that one made it, one did not, on top of an already rough year, etc just introduces an even greater uncertainty overall. Personally, I won't be sticking my head in the sand.
It seems like the engine is not to blame. An abnormal function of the tank pressurization system is suspected.
"How to explain abnormal pressure only in one chamber of the four by abnormal tank pressurization?""If you drive the turbopump in cavitation conditions, everything is possible.""Pressurization was OK, but close to the lower margin. Pressure at the engine's feed was just 0.11 kgf/cm^2 more than the operating margin. This engine with old design of the inlet manifold, there were problems with that manifold's soldering. A firing test was failed once with this version. After that all engines in that run were scrutinized, and one got a chamber replaced. The manifold was redesigned after that test. Common sense's call was to cull away this engine, but CADB have given their clearance again, and everybody agreed with them due to number of reasons, and chief customers also signed it off."
(commenting on Putin's opinion that quality checks should be more strict in the space industry)I want to say that "it began when the space industry was transformed to self sufficiency and profit has become paramount". A design bureau can no longer plan any expenses for failed tests in its budget. No customer would ever agree to pay for such things. All difference should now be paid away from the profit of the bureau. And how much of that profit do we have? We have to pull the belt in on everything! At the same time, in addition to losses we suffer from accidents, we can "go negative" due to "nonfulfillment of a plan". Go try to disqualify any satellite/rocket/engine for your own expense, if you can't deny there's a sort of workaround for an issue.When CPUs are produced, the percentage of culling is between 20% and 80%, and when it comes to rocketry, they demand 0% of rejected production and "triple nine" reliability...They on top like to talk about quality, but they don't like to provide for the much desired quality and pay for it.
QuoteThey on top like to talk about quality, but they don't like to provide for the much desired quality and pay for it.
They on top like to talk about quality, but they don't like to provide for the much desired quality and pay for it.
Has any official statement been released about the cause for this failure?
(commenting on Putin's opinion that quality checks should be more strict in the space industry)I want to say that "it began when the space industry was transformed to self sufficiency and profit has become paramount". A design bureau can no longer plan any expenses for failed tests in its budget. No customer would ever agree to pay for such things. All difference should now be paid away from the profit of the bureau....They on top like to talk about quality, but they don't like to provide for the much desired quality and pay for it.
At the last stages of the investigation committee unanimously concluded that the cause of the fall, "Meridian" - the human factor. The core committee included staff from the emergency investigation of the Academy named after Mozhaisky, 4th Central Research Institute for the Defense Ministry and other institutions head-space industry. Experts Voronezh and Samara Space NGOs "Progress" is not included in the commission. They were admitted to the inquiry only as observers. - A careful hearing by the commission members found that the satellite fell because of the disclosure of the combustion chamber, - the source of Life News Roskomose. - This was due to the imperfection of engine technology at the Voronezh factory. This type of engine was not invented so long ago, and have not considered spetsialistyk all possible extreme impacts. In other words, when you start the climb and missile carrier revealed weld the combustion chamber. Because of this began to occur a loss of fuel, which caused the engine to stop already at a decent height. Officially, the emergency commission completes its investigation on Monday. However, the organization has called the guilty - it's the Voronezh Mechanical Plant "Space". Specific perpetrators will not be named. The experts agreed that the fall of the satellite - the wines of the organization as a whole. Recall at the Voronezh factory "Cosmos" made liquid rocket engines RD-0110 RD-0210, RD-0211, RD 0212, RD-58. Engines of this plant always considered the highest-quality and reliable in operation as long as in Russia, one after another did not happen five accidents during the launching. Half an hour after the launch of "Meridian" has failed. The rocket, which was to bring the unit into the proper orbit, suddenly ceased to rise, had to retire when the third stage. Run the "Meridian" was a failure for the same reason that had been lost four staff running up to it.
Soyuz-2.1b ? All previous Meridian had been orbited by Soyuz-2.1a… Do you know the reason of he change ?
