Our experience in flying to the 100k’+ region with peak speeds in the Mach
2.5-3.5 domain suggests heating highly overrated. We are flying largely
composite airframes with modest grade epoxy with composite (fiberglass)
nosecones with an aluminum tip - VK shape.
We have seen no signs of nosecone heating … and the only heat effects on the
airframe we have seen has been on heavy paint on the sustainer body about 3’
back from the nosecone tip .. where it appears the shockwave returns to the
body. It got a bit smeared. Hope to actually, finally fly an instrumented
nosecone this summer to measure nosecone heating.
K
On Apr 5, 2017, at 4:33 PM, Team Icarus SDSU <rocketteamicarus@xxxxxxxxx>
wrote:
This question is also of interest to our projects.
It's a couple years from launch, but Icarus 3 is likely to remain in the
M=3.0-4.0 range for the first 100,000' of its flight; significant heating is
expected. We need to perform more in-depth analysis, but the current plan is
to build the dart section from lathe-turned inconel.
Alex Lewis
On Tue, Apr 4, 2017 at 6:22 PM, William Claybaugh <wclaybaugh2@xxxxxxxxx
<mailto:wclaybaugh2@xxxxxxxxx>> wrote:
Do (AR) nose tips see the kind of heating that would require inconel or the
like?
I've wondered if USC/RPL's titanium nose tips are justified for a Mach 5
mission w/ a very short heat pulse....
To be clear, I have not done my own analysis, I'm asking two questions.
Bill
On Tue, Apr 4, 2017 at 7:01 PM Ben Brockert <wikkit@xxxxxxxxx
<mailto:wikkit@xxxxxxxxx>> wrote:
I visited Atlantic Precision a couple years ago, one of the few shops in the
US with multiple EOS DMLS machines, and they were actively printing parts for
the RL-10 even back then. Printing the chamber is big and flashy, but there's
a lot of utility in cranking out highly detailed inco or haynes parts.
For any part with moderate complexity of the nickel alloys it's now cheaper
to print and lightly post-machine than to machine from solid material, even
at small production quantities.
That is of relevance to AR because a one-off printed and sanded nickel alloy
nose tip for a higher performance hobby rocket should quite affordable,
especially if you shop around and make it clear that you're not in a rush for
the part.
On Tuesday, April 4, 2017, Dave Klingler <davek@xxxxxxxxxxxxxxxx
<mailto:davek@xxxxxxxxxxxxxxxx>> wrote:
Ehhhh…one can always ask. Sometimes people like to talk about where they’re
headed. :)
Dave
On Apr 4, 2017, at 1:17 PM, William Claybaugh <wclaybaugh2@xxxxxxxxx <>>
wrote:
Dave:
Anyone privy to such information is likely subject to a non-disclosure
agreement....
Bill
On Tue, Apr 4, 2017 at 12:24 PM Dave Klingler <davek@xxxxxxxxxxxxxxxx <>>
wrote:
I just saw an article over at parabolicarc about AJR's first 3d-printed
thrust chamber firing. I’m trying to decide whether, from what I’ve read,
they’re substituting copper for stainless in a few spots.
I think design changes are probably unlikely this early, but at the very
least the new manufacturing process opens up the way for different materials
and more elaborate cooling passages that wouldn’t be possible using the old
tube benders. Is anyone on this list privy to what sort of plans AJR has
for higher chamber pressures or other improvements to the RL-10? What’s the
schedule for doing complete engine certification?
Dave Klingler
