Blue Origin changes engines for New Glenn second stage
Capitalism in space: In order to maintain its goal of launch its orbital New Glenn rocket by 2020, Blue Origin has changed the engine it will use in the rocket’s second stage from a version of its main BE-4 engine to new version of their already developed BE-3 engine, used in their reusable New Shepard suborbital spacecraft.
A Blue Origin executive told SpaceNews the company is shelving development of a vacuum-optimized version of BE-4 and will instead use vacuum-optimized versions of flight-proven BE-3 engines for New Glenn’s second stage and optional third stage. “We’ve already flown BE-3s, and we were already in the development program for BE-3U as the third stage for New Glenn,” said Clay Mowry, Blue Origin’s vice president of sales, marketing and customer experience. “It made a lot of sense for us to switch to an architecture where we get there faster for first flight.”
The BE-3U is the upper stage variant of the liquid hydrogen-fueled BE-3 engine that has powered Blue Origin’s reusable New Shepard spacecraft on seven suborbital test flights since its 2015 debut. Mowry said switching to the BE-3U for New Glenn’s second stage will allow Blue Origin to conduct the rocket’s first launch in the fourth quarter of 2020. He declined to say how much time the engine change saves compared to the original configuration.
This quiet change, which the company made with no fanfare, carries with it some significant information as well as important ramifications. First, the BE-3 engine is less powerful than the planned BE-4, which is why they will use two BE-3 engines in the second stage instead of one BE-4, while also extending the length of the stage to accommodate more fuel. Though they claim the change will increase the rocket’s range, I suspect however that even with these changes New Glenn’s overall orbital payload capacity will be reduced.
Second, the change indicates that development of the BE-4 engine is proceeding slower than expected, threatening their 2020 launch goal. They have had one test failure that set them back, and the change suggests to me that they are having issues with making the engine restartable.
Third, if they have problems making the BE-4 engines restartable, this means their plans to reuse the first stage of New Glenn will be impacted. While those first stage engines do not need to restart on any single flight, reusing them requires this capability.
Fourth, problems with the BE-4 might cause ULA to reject it and choose Aerojet Rocketdyne’s AR-1 engine for its new Vulcan rocket. Up to now ULA has indicated it prefers the BE-4. These issues might change that.
Fifth, this change, combined with the continuing lack of New Shepard test flights, suggests that the company is increasingly considering abandoning this suborbital spacecraft.
I am doing a lot of speculating here, and could be very wrong on many if not all of these suppositions. We shall have to wait and see.
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 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
Capitalism in space: In order to maintain its goal of launch its orbital New Glenn rocket by 2020, Blue Origin has changed the engine it will use in the rocket’s second stage from a version of its main BE-4 engine to new version of their already developed BE-3 engine, used in their reusable New Shepard suborbital spacecraft.
A Blue Origin executive told SpaceNews the company is shelving development of a vacuum-optimized version of BE-4 and will instead use vacuum-optimized versions of flight-proven BE-3 engines for New Glenn’s second stage and optional third stage. “We’ve already flown BE-3s, and we were already in the development program for BE-3U as the third stage for New Glenn,” said Clay Mowry, Blue Origin’s vice president of sales, marketing and customer experience. “It made a lot of sense for us to switch to an architecture where we get there faster for first flight.”
The BE-3U is the upper stage variant of the liquid hydrogen-fueled BE-3 engine that has powered Blue Origin’s reusable New Shepard spacecraft on seven suborbital test flights since its 2015 debut. Mowry said switching to the BE-3U for New Glenn’s second stage will allow Blue Origin to conduct the rocket’s first launch in the fourth quarter of 2020. He declined to say how much time the engine change saves compared to the original configuration.
This quiet change, which the company made with no fanfare, carries with it some significant information as well as important ramifications. First, the BE-3 engine is less powerful than the planned BE-4, which is why they will use two BE-3 engines in the second stage instead of one BE-4, while also extending the length of the stage to accommodate more fuel. Though they claim the change will increase the rocket’s range, I suspect however that even with these changes New Glenn’s overall orbital payload capacity will be reduced.
Second, the change indicates that development of the BE-4 engine is proceeding slower than expected, threatening their 2020 launch goal. They have had one test failure that set them back, and the change suggests to me that they are having issues with making the engine restartable.
Third, if they have problems making the BE-4 engines restartable, this means their plans to reuse the first stage of New Glenn will be impacted. While those first stage engines do not need to restart on any single flight, reusing them requires this capability.
Fourth, problems with the BE-4 might cause ULA to reject it and choose Aerojet Rocketdyne’s AR-1 engine for its new Vulcan rocket. Up to now ULA has indicated it prefers the BE-4. These issues might change that.
Fifth, this change, combined with the continuing lack of New Shepard test flights, suggests that the company is increasingly considering abandoning this suborbital spacecraft.
I am doing a lot of speculating here, and could be very wrong on many if not all of these suppositions. We shall have to wait and see.
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 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
“First, the BE-3 engine is less powerful than the planned BE-4, which is why they will use two BE-3 engines in the second stage instead of one BE-4, while also extending the length of the stage to accommodate more fuel.”
The BE-3 was going to be used anyway, in a third stage, so the LHy/LOX plumbing would need to be built into the launch pad anyway. The higher specific impulse of LHy/LOX propellant will give the upper stages more total capability as well. The extension of the second stage is to accommodate the lower density of the Liquid Hydrogen, …with a density of .0709, instead of the .55 of Liquid Methane at the boiling point.
Since the first stage will do most all of the lofting to orbit, and can make up gravity losses easier with its larger number of engines, the lower thrust of 2 BE-3Us thrusting in a horizontal direction, will just mean a longer burn time. This will be especially important during the launches that only the first stage is reusable. Better to expend just 2 BE-3Us than to expend even one far larger BE-4.
“They have had one test failure that set them back, and the change suggests to me that they are having issues with making the engine restartable.”
Relatively unlikely with cryogenic propellant. Usually spark-based systems are quite adequate with LHy/LOX or MethaLOX propellants, over a wide range of pressures and mixture ratios, and those fancy spark plugs are relatively easy to make reusable.
“While those first stage engines do not need to restart on any single flight, reusing them requires this capability.”
At least *some* of the 7 first stage engines *must* reignite for the landing, and as I said above, that *should*not* be the problem.
“Fifth, this change, combined with the continuing lack of New Shepard test flights, suggests that the company is increasingly considering abandoning this suborbital spacecraft.”
In fact, it seems probable that the “Blue Moon” vehicle, mentioned more than once by Bezos and others as a Lunar Lander, will be yet another version of the BE-3-powered New Shepard vehicle. I would find it far more believable that they are splitting engineering time between finalizing New Shepard, developing it as a legless and finless third stage for New Glenn, and developing it as a lunar lander without the ring-sail fin of the New Sheperd for Blue Moon.
Only so many man-hours in an engineering team’s day are available, …and if no great new market for the finned and legged New Shepard sub-orbital has appeared, it makes sense to move other developments of it along as well. It’s not like Bezos is in a hurry to pull in revenue from the sub-orbital vehicle, though experience with multiple launches couldn’t hurt his launch team confidence.
Tom Billings: Thank you for the clarifications and analysis. Most appreciated, especially since I am not an engineer.