Unexpectedly high RASAero estimate for a two-stage rocket.

Great idea [emoji362]
When I shop for a pickup I always ask what kind of mileage the engine would get without the rest of the truck.

RGClark said:

So I'll take a stab at making a RASP ENG file for the motor and then doing a OpenRocket and/or RASAero sim.

Click to expand...

Like this?

Thanks for that.

Bob Clark

I did an OpenRocket sim using the CTI booster motor for the SpaceLoft rocket, as well as for a rocket with all the payload in the nosecone. They show in both cases a ca. 350 kg total gross mass rocket, i.e., including payload, could be lofted to ca. 100 km altitude.

Sims attached.

Bob Clark

View attachment SpaceLoft XL - booster only.ork

View attachment SpaceLoft XL.ork

jsdemar said:

Like this?

; Cesaroni Booster motor for UP Aerospace.
; @File: CTI_UPA-264-C.eng, @Pts-I: 42, @Pts-O: 31, @Sm: 0, @CO: 5%
; @TI: 438207.0, @TIa: 437890.0, @TIe: -0.05%, @ThMax: 52454.9, @ThAvg: 37051.4, @Tb: 11.827
; Exported using ThrustCurveTool, www.ThrustGear.com
S37029 265 3018 P 186.8801 242.672 CTI
0.037 540.773
0.061 1406.008
0.073 13086.69
...
​

Click to expand...

Perhaps you could add this to the Thrustcurve.org collection of motor thrust specifications:

https://www.thrustcurve.org/contribute.shtml

so others could do sims using this S-class Cesaroni motor.

Bob Clark

Steve Shannon said:

Great idea [emoji362]
When I shop for a pickup I always ask what kind of mileage the engine would get without the rest of the truck.

Click to expand...

You too? :eyepop:

pondman said:

You too? :eyepop:

Click to expand...

I confess. It was meant to be humorous. [emoji851]

Steve Shannon said:

I confess. It was meant to be humorous. [emoji851]

Click to expand...

It was......

RGClark said:

Perhaps you could add this to the Thrustcurve.org collection of motor thrust specifications:

https://www.thrustcurve.org/contribute.shtml

so others could do sims using this S-class Cesaroni motor.

Bob Clark

Click to expand...

The Thrustcurve.org site is only for certified commercial motors manufactured under NFPA 1125, and used under NFPA 1122/1127. The commercial safety codes go to a maximum of an 'O' motor.

RGClark said:

Perhaps you could add this to the Thrustcurve.org collection of motor thrust specifications:

https://www.thrustcurve.org/contribute.shtml

so others could do sims using this S-class Cesaroni motor.

Bob Clark

Click to expand...

No we will not be doing that. Thrustcurve is purposely being limited to O motors and below- hence motors that can be certified.

Nice article here on the Princeton Rocketry Teams attempt at a suborbital space flight. The launch is scheduled for Sunday, May 27th at 9am Eastern Time, with Monday, May 28th as the backup date:

Princeton Rocketry Club to Launch First Student Rocket into Outer Space.
Wednesday, May 23, 2018
by Ian D. Deas
https://odus.princeton.edu/news/princeton-rocketry-club-launch-first-student-rocket-outer-space

The launch will be live streamed on Spaceport America's Facebook page:

https://www.facebook.com/spaceportNM

Bob Clark

RGClark said:

Nice article here on the Princeton Rocketry Teams attempt at a suborbital space flight. The launch is scheduled for Sunday, May 27th at 9am Eastern Time, with Monday, May 28th as the backup date:

Princeton Rocketry Club to Launch First Student Rocket into Outer Space.
Wednesday, May 23, 2018
by Ian D. Deas
https://odus.princeton.edu/news/princeton-rocketry-club-launch-first-student-rocket-outer-space

The launch will be live streamed on Spaceport America's Facebook page:

https://www.facebook.com/spaceportNM

Bob Clark

Click to expand...

I suspect they know that there are some really bad upper level winds on those days. Lotsa luck.

Jim

JimJarvis50 said:

I suspect they know that there are some really bad upper level winds on those days. Lotsa luck.

Jim

Click to expand...

Is there a web page that specifically gives high altitude winds at the site?

Bob Clark

RGClark said:

Is there a web page that specifically gives high altitude winds at the site?

Bob Clark

Click to expand...

Yes. Twice daily NWS soundings. And historical data. Served at the university of Wyoming.. Google "Wyoming upper atmosphere soundings".

RGClark said:

Is there a web page that specifically gives high altitude winds at the site?

Bob Clark

Click to expand...

This is my favorate site. You can get the forecast for almost anything by many of the weather models.

https://www.windy.com/?200h,31.410,-104.854,5,m:ez4adcW

Winds for noon Sunday and Monday are attached. Not much mystery in this forecast.

Jim

JimJarvis50 said:

This is my favorate site. You can get the forecast for almost anything by many of the weather models.

https://www.windy.com/?200h,31.410,-104.854,5,m:ez4adcW

Winds for noon Sunday and Monday are attached. Not much mystery in this forecast.

Jim

Click to expand...

Thanks. I’ll ask if they took that into account.

Bob Clark

RGClark said:

Thanks. I’ll ask if they took that into account.

Bob Clark

Click to expand...

Yes. They did.

RGClark said:

Nice article here on the Princeton Rocketry Teams attempt at a suborbital space flight. The launch is scheduled for Sunday, May 27th at 9am Eastern Time, with Monday, May 28th as the backup date:

Princeton Rocketry Club to Launch First Student Rocket into Outer Space.
Wednesday, May 23, 2018
by Ian D. Deas
https://odus.princeton.edu/news/princeton-rocketry-club-launch-first-student-rocket-outer-space

The launch will be live streamed on Spaceport America's Facebook page:

https://www.facebook.com/spaceportNM

Bob Clark

Click to expand...

That live streaming start time should be 10am Eastern, 8am Mountain time.

Bob Clark

Live streaming now!

https://www.facebook.com/pg/spaceportNM/videos/?ref=page_internal


Bob Clark

RGClark said:

Live streaming now!

https://www.facebook.com/pg/spaceportNM/videos/?ref=page_internal


Bob Clark

Click to expand...

Winds 50 knots average from the SW, with 100 knot shear on the way through the tropopause.

https://weather.uwyo.edu/cgi-bin/so...AR=2018&MONTH=05&FROM=2712&TO=2712&STNM=72365

Continuing discussion here:

https://www.rocketryforum.com/showt...a-suborbital-space-shot&p=1788509#post1788509

JimJarvis50 said:

This is my favorate site. You can get the forecast for almost anything by many of the weather models.

https://www.windy.com/?200h,31.410,-104.854,5,m:ez4adcW

Winds for noon Sunday and Monday are attached. Not much mystery in this forecast.

Jim

Click to expand...

Unconfirmed reports are that the second stage didn't light. Speculation is that the high upper level winds changed the attitude of the rocket causing an automatic cutoff of engine ignition.

If so, then the way is still open for an experienced amateur to be first do a flight to suborbital space using commercial motors. It would have to be a minimal diameter design, i.e., without airframes to save weight. Attachment of fins could be done via a fin can.

Some observers of amateur rocketry have questioned whether the famous launch to suborbital space in 2004 by the CXST team should be considered an "amateur" launch to space since there were professional engineers on their team. In that case, under that interpretation, the title of first amateur launch to space could still be considered open.

On the Princeton team's technical documents page they gave the document they had to file with the FAA that allowed them to launch from Spaceport America without doing recovery of the booster stage. A member of the team has said they weren't required to do recovery of the sustainer stage either for a Spaceport America launch but wanted to because it contained the payload:

https://rockets.princeton.edu/spaceshot-technical-documentation



Bob Clark

View attachment Modified FourCarbYen - N5800 to N1100,ver 2.ork

RGClark said:

Unconfirmed reports are that the second stage didn't light. Speculation is that the high upper level winds changed the attitude of the rocket causing an automatic cutoff of engine ignition.

Click to expand...

Already discussing this in the correct topic thread here:
https://www.rocketryforum.com/showt...sity-attempt-at-a-suborbital-space-shot/page2