tag:blogger.com,1999:blog-19394281.post7415928827379145949..comments2023-10-18T08:43:10.620-04:00Comments on The Flame Trench space news and analysis: Weather slightly better for 2nd launch tryC Perezhttp://www.blogger.com/profile/13916832810035419167noreply@blogger.comBlogger4125tag:blogger.com,1999:blog-19394281.post-24647503563676712892009-08-26T12:48:15.461-04:002009-08-26T12:48:15.461-04:00Maybe that's it, Anon. I know I hear the noise...Maybe that's it, Anon. I know I hear the noise before the hydrogen burn ignitors fire. I thought it was around t-13 but maybe it's a few seconds before. Is that something the audio would be able to pick up? I wish I had the last launch still on my TiVo to check.Unknownhttps://www.blogger.com/profile/11700662024219279498noreply@blogger.comtag:blogger.com,1999:blog-19394281.post-31084394219011610132009-08-26T11:30:40.372-04:002009-08-26T11:30:40.372-04:00The SRB APUs are the more likly source. They are c...The SRB APUs are the more likly source. They are called HPUs (Hydraulis Power Units) they start just after T-18 sec.Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-19394281.post-53164902770670433022009-08-25T15:08:00.096-04:002009-08-25T15:08:00.096-04:00Mark:
I wonder whether you might be hearing the A...Mark:<br /><br />I wonder whether you might be hearing the APUs? They start chugging like a railroad train at T-Minus five and make a hitch-pitched whine closer to launch, so I suspect that's what you are hearing..<br /><br />ToddTodd Halvorsonnoreply@blogger.comtag:blogger.com,1999:blog-19394281.post-50617612921222476542009-08-25T13:22:51.853-04:002009-08-25T13:22:51.853-04:00I've always meant to ask this question and did...I've always meant to ask this question and didn't want to clog the live box with this. Between the time the sound suppresion water system and the hydrogen burn ingitors start, I seem to hear a high-pitched noise. I would guess it's around the t-13 second mark. What is this? I know those two are armed around the one minute mark. Perhaps it's the ignitors getting ready to fire at Unknownhttps://www.blogger.com/profile/11700662024219279498noreply@blogger.com