Since these engines don’t look to be gimbaled, a high pitch or yaw rate indicates a single chamber explosion or a single chamber thrust failure (due to injector clog or some sort of plumbing related failure). These failure modes are very significantly different but would result in the same high pitch/yaw rate and pressure spike that has been so far correctly or incorrectly reported.
Quote from: oldAtlas_Eguy on 12/24/2011 05:34 pmSince these engines don’t look to be gimbaled, a high pitch or yaw rate indicates a single chamber explosion or a single chamber thrust failure (due to injector clog or some sort of plumbing related failure). These failure modes are very significantly different but would result in the same high pitch/yaw rate and pressure spike that has been so far correctly or incorrectly reported.The main chambers aren't gimbaled, but the vernier chambers do gimbal to provide steering. The verniers may be fed from the same turbopump assembly as the main chambers, so possible failure modes resulting in loss of steering seem numerous. - Ed Kyle
Quote from: Prober on 12/24/2011 03:13 pmproblem, we have is failures in both engines now. What is common in both set of engines?Possibly just personnel.
problem, we have is failures in both engines now. What is common in both set of engines?
This is a dumb question, but several posters have referred to this failure as an "explosion" of one form or another. How do you get telemetry for a long enough period that indicates the stage pitched over enough to gimbal lock? Based on what has been posted it sounds more like a rupture (maybe violent) in either the plumbing or one the chambers. It does not sound like an immediate RUD that shredded the stage, something more akin to the failure that doomed the second Delta III flight.
From Analoly Zak's site:QuoteLatest update: According to industry sources, the analysis of available telemetry on the fuel line pressure before the entrance to the engine's injection system indicated a possible bulging of the combustion chamber No. 1, leading to its burn through and a catastrophic fuel leak.
Latest update: According to industry sources, the analysis of available telemetry on the fuel line pressure before the entrance to the engine's injection system indicated a possible bulging of the combustion chamber No. 1, leading to its burn through and a catastrophic fuel leak.
Quote from: kevin-rf on 12/25/2011 12:34 amThis is a dumb question, but several posters have referred to this failure as an "explosion" of one form or another. How do you get telemetry for a long enough period that indicates the stage pitched over enough to gimbal lock? Based on what has been posted it sounds more like a rupture (maybe violent) in either the plumbing or one the chambers. It does not sound like an immediate RUD that shredded the stage, something more akin to the failure that doomed the second Delta III flight.The "explosion" references may be misquotes of this post ...Quote from: baldusi on 12/23/2011 05:04 pmFrom Analoly Zak's site:QuoteLatest update: According to industry sources, the analysis of available telemetry on the fuel line pressure before the entrance to the engine's injection system indicated a possible bulging of the combustion chamber No. 1, leading to its burn through and a catastrophic fuel leak.... which sounds very much like what happened to the Delta III.
The RD-0124 doesn't have verniers I decided to do some research and apparently the nozzles do gimbal along a single axis.http://www.russianspaceweb.com/rd0124.htmlLoss of one of the actuators would result in loss of control.
Looks like eight fragments of Meridian have been located in the Novosibirsk region:http://www.1tv.ru/news/techno/194869
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).
