From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-ej1-x636.google.com (mail-ej1-x636.google.com [IPv6:2a00:1450:4864:20::636]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by lists.bufferbloat.net (Postfix) with ESMTPS id 255803B29D for ; Thu, 11 May 2023 12:24:45 -0400 (EDT) Received: by mail-ej1-x636.google.com with SMTP id a640c23a62f3a-965ab8ed1c0so1456329566b.2 for ; Thu, 11 May 2023 09:24:45 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20221208; t=1683822284; x=1686414284; h=cc:to:subject:message-id:date:from:references:in-reply-to :mime-version:from:to:cc:subject:date:message-id:reply-to; bh=PdMeEJIv2evYAc2qr7XG/toB2c/+H8KKT3MIyIX83BM=; b=F0WWXMtxk9hD7atgpo/MFRhNr9X5NJWoLyh06RGf//dmeE7rNw680szyMplmm4khG1 B4L6eIjToR6cmm7Yqbq4hXS3GYG2rp5NUOX7gi2Mhho4KueMg8tjRWKvX4d7ZOpR9Xnd T4TCHJSNX7ZwN/AsFeOHYkkcajvPN45Iorqgl/VCM5iWBE7DjfUmK8CCzmuKQpJ9nJgC /LTM+bNG4/1v4cFXMNGf2zh/wFzmBMmIB5vY6/Y4B7OtGAZMvSusllfrJLuJFDGU+Q7W azCTgtrnWw0u1QzHW042iHezkkhR4XWus7lQIIafkF9U+JYFW9mlszTQdYDRTAJpLpdA roBQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20221208; t=1683822284; x=1686414284; h=cc:to:subject:message-id:date:from:references:in-reply-to :mime-version:x-gm-message-state:from:to:cc:subject:date:message-id :reply-to; bh=PdMeEJIv2evYAc2qr7XG/toB2c/+H8KKT3MIyIX83BM=; b=Nvea4yhsV71IlGoP0jdkTnXecROkfYi8okUNbhSH5xt1EV+3FqQ1e85HaXwzucpfok 8JE4/HsmDjEZYsOQTF+tLdO/vBWitE+0aI4ogOOpbNl0dLAt2AN7ApVzvvxV4RVU9vrf xdSrJnpuLtdoiPj76Xqa7g1+ymzJiCSL4rz0dlKrxytJ9gLtWZHx7t5X1WRIdO/Jgr2A NXDBx1quVfspM2lglCXCfOdzFDrRm51Ir1/xS7ggGTq9gkcfaq02Uw8bcz4nOj1d0/SX csjkfMFFj247ar3TtL66C/ugq3/4/BFN8+MJo9cuxENx+qNmuDuCr//noTxVa2IA3W83 kcuA== X-Gm-Message-State: AC+VfDyss91jn1PqRB4eWRMCp/Y05+YtW1XNvD6RoRtswuiP6CSLoNP/ /DZZamD7WumlDnbAJFLUXmMwzRoGxklntFV6pllks8CR X-Google-Smtp-Source: ACHHUZ62nP9TmaYunhu8eAbVtnC+Cbzf6Gba7xVdqneXzgir9qnP4egNzPI8vYYzvP4SdTykDK7ZL2v1LLD8afCctXk= X-Received: by 2002:a17:907:25c8:b0:94a:ac4b:e11b with SMTP id ae8-20020a17090725c800b0094aac4be11bmr16757191ejc.39.1683822283948; Thu, 11 May 2023 09:24:43 -0700 (PDT) MIME-Version: 1.0 Received: by 2002:a05:6f02:40a1:b0:4b:d6cb:f0f5 with HTTP; Thu, 11 May 2023 09:24:43 -0700 (PDT) In-Reply-To: References: <1682455200.058420642@apps.rackspace.com> From: Sauli Kiviranta Date: Thu, 11 May 2023 19:24:43 +0300 Message-ID: To: David Lang Cc: "David P. Reed" , starlink@lists.bufferbloat.net Content-Type: text/plain; charset="UTF-8" Subject: Re: [Starlink] some post Starship launch thoughts X-BeenThere: starlink@lists.bufferbloat.net X-Mailman-Version: 2.1.20 Precedence: list List-Id: "Starlink has bufferbloat. Bad." List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 11 May 2023 16:24:45 -0000 Somehow this ended up in spam by gmail. What you explained makes it even more remarkable, I would not indeed call it being overlooked. That is just plain failure of scaling whatever they learned from those iterations. It is definitely not obvious, just remarkable. Thanks for sharing these details! Best regards, Sauli On 4/26/23, David Lang wrote: > On Wed, 26 Apr 2023, Sauli Kiviranta via Starlink wrote: > >> It was interesting to see that such a "basic" thing as the launch pad >> structure was overlooked as a rather large problem vector. Even if it >> was recognized as an issue, that it turned out to be a majestic >> borderline catastrophic issue was surprise to me. Easy to overlook >> everything when scaling up. There is a great book on the topic of >> systems and their scaling parts when sizes change "Scale: The >> Universal Laws of Growth" by Geoffrey West, highly recommended. > > It wasn't overlooked, they did a 7 engine static fire, it damaged the pad, > so > they improved it, they did a 14 engine static fire and it damaged it again, > so > they improved it again, they did a 31 engine 50% power static fire with > minimal > pad damage and had other blocks of material mounted in the engine exhaust at > > McGreggor. They just failed to catch some inflection point between the 50% > power > test and the full power test. They expected some damage to the pad, but not > > nearly as much as what happened. > > David Lang >