ABL preparing for second launch attempt of its RS1 rocket
ABL’s redesigned rocket launch mount
Since its first test launch of its RS1 rocket failed in January 2023, ABL has spent the last ten months doing major revisions of the rocket’s launch mount as well as preparing an upgraded new rocket for a second test launch attempt, expected in the coming months.
This information comes from a long update posted by the company’s CEO, Harry O’Hanley on October 25, 2023.
It appears failure occurred because of a fire at the base of the rocket after liftoff, which in turn was caused by the small size of the rocket’s launch mount.
By analyzing video and data, we formulated a leading theory behind the source of the fire. Our hypothesis centered around the Launch Mount, which is the GS0 assembly that raises and lowers the vehicle. It was designed to fit fully assembled inside a shipping container. While this made transport simple, it resulted in the rocket being held close to the ground.
We believe the compact Launch Mount and proximity of RS1 to the ground restricted the flow of engine exhaust gas. This caused plume recirculation and drove pressures and temperatures beneath the rocket to exceed the RS1 base heat shield design capability. The hot combustion gases breached the aft heat shield and initiated the engine compartment fire. We corroborated this theory with a variety of tests and analyses, including multi-species CFD performed both in-house and by an independent partner.
The graphic to the right, rearranged and annotated to post here, shows the new larger mount. Because of the time it has taken to make that launch mount upgrade, the company also decided to fly its next version of RS1 on this second test launch, rather than the backup rocket from the first launch. This upgraded RS1 has 20% more thrust with a detachable engine section that makes access to it much easier.
O’Hanley made no mention of a specific target launch date from the Kodiak spaceport in Alaska, but his post implies the launch is coming very soon.
On Christmas Eve 1968 three Americans became the first humans to visit another world. What they did to celebrate was unexpected and profound, and will be remembered throughout all human history. Genesis: the Story of Apollo 8, Robert Zimmerman's classic history of humanity's first journey to another world, tells that story, and it is now available as both an ebook and an audiobook, both with a foreword by Valerie Anders and a new introduction by Robert Zimmerman.
The print edition can be purchased at Amazon. from any other book seller, or direct from my ebook publisher, ebookit.
The ebook is available everywhere for $5.99 (before discount) at amazon, or direct from my ebook publisher, ebookit. If you buy it from ebookit you don't support the big tech companies and the author gets a bigger cut much sooner.
The audiobook is also available at all these vendors, and is also free with a 30-day trial membership to Audible.
"Not simply about one mission, [Genesis] is also the history of America's quest for the moon... Zimmerman has done a masterful job of tying disparate events together into a solid account of one of America's greatest human triumphs."--San Antonio Express-News
ABL’s redesigned rocket launch mount
Since its first test launch of its RS1 rocket failed in January 2023, ABL has spent the last ten months doing major revisions of the rocket’s launch mount as well as preparing an upgraded new rocket for a second test launch attempt, expected in the coming months.
This information comes from a long update posted by the company’s CEO, Harry O’Hanley on October 25, 2023.
It appears failure occurred because of a fire at the base of the rocket after liftoff, which in turn was caused by the small size of the rocket’s launch mount.
By analyzing video and data, we formulated a leading theory behind the source of the fire. Our hypothesis centered around the Launch Mount, which is the GS0 assembly that raises and lowers the vehicle. It was designed to fit fully assembled inside a shipping container. While this made transport simple, it resulted in the rocket being held close to the ground.
We believe the compact Launch Mount and proximity of RS1 to the ground restricted the flow of engine exhaust gas. This caused plume recirculation and drove pressures and temperatures beneath the rocket to exceed the RS1 base heat shield design capability. The hot combustion gases breached the aft heat shield and initiated the engine compartment fire. We corroborated this theory with a variety of tests and analyses, including multi-species CFD performed both in-house and by an independent partner.
The graphic to the right, rearranged and annotated to post here, shows the new larger mount. Because of the time it has taken to make that launch mount upgrade, the company also decided to fly its next version of RS1 on this second test launch, rather than the backup rocket from the first launch. This upgraded RS1 has 20% more thrust with a detachable engine section that makes access to it much easier.
O’Hanley made no mention of a specific target launch date from the Kodiak spaceport in Alaska, but his post implies the launch is coming very soon.
On Christmas Eve 1968 three Americans became the first humans to visit another world. What they did to celebrate was unexpected and profound, and will be remembered throughout all human history. Genesis: the Story of Apollo 8, Robert Zimmerman's classic history of humanity's first journey to another world, tells that story, and it is now available as both an ebook and an audiobook, both with a foreword by Valerie Anders and a new introduction by Robert Zimmerman.
The print edition can be purchased at Amazon. from any other book seller, or direct from my ebook publisher, ebookit. The ebook is available everywhere for $5.99 (before discount) at amazon, or direct from my ebook publisher, ebookit. If you buy it from ebookit you don't support the big tech companies and the author gets a bigger cut much sooner.
The audiobook is also available at all these vendors, and is also free with a 30-day trial membership to Audible.
"Not simply about one mission, [Genesis] is also the history of America's quest for the moon... Zimmerman has done a masterful job of tying disparate events together into a solid account of one of America's greatest human triumphs."--San Antonio Express-News
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