Save the text file as a .csv file and read straight into Excel. I just did that with your .txt file.
You then select the data from you column headings down and insert as a scatter chart. See below.
I haven't added axis titles or fully separated the data on left/right vertical axes. I'll leave that for you.
If you saw this graph how would you describe this flight ?View attachment 438656
I plotted velocity only
I'd say you had a motor event that pressurized your avbay, but fell short of a CATO.
View attachment 438658
That's interesting how did you come up with that?
I plotted velocity only with an expanded scale and velocity looks pretty constant for duration of descent. Maybe you popped main at apogee?
View attachment 438659
I plotted velocity only with an expanded scale and velocity looks pretty constant for duration of descent. Maybe you popped main at apogee?
View attachment 438659
Looks like a typical nominal single deploy data trace. Also looks just like my RRC3 data traces when I have an unintended main-at-apogee event in dual deploy birds. I have a Mad Cow 4" DX3 that took 4 flights before I got the magic set up on it where dual deploy worked every time without shaking the main out before the intended altitude.
Only if you planned it that way. Otherwise something wrong with your setup.. Drogue harness too short? No NC retention (shear pins)? Overaggressive drogue charge?Is Main at apogee that common?
This is the same Ebay that ive flown a hand full of times DD without issue...
Could a very strong gust of wind into the av-bay account for the pressure spike? Neither charges were fired until well into the flight and if the motor started to leak, I'd expect a very different altitude plot.The altitude ramps up like you'd expect, then drops down almost to zero, then rushes back up a reasonable ascent curve. The velocity is just the 1st derivative of the altitude, so it highlights the slope. The unfiltered data is the same, so that broad dip is something broad in time, not a single big jolt being smoothed by the filtering process. If it were a jolt, I say something shifted, or blew off in flight. It's not at the right speed for a mach issue. For the altitude to drop, it means the pressure must be going up - so where could that come from: motor leakage forward, short of failure, a early deployment charge short of popping the nosecone (but I'd expect that to be narrower), or maybe a quirk of your nosecone or avbay design that is funneling airflow in to the avbay (but I'd expect that to be a function(velocity) and it doesn't look like that to me.)
I'd say you had a motor event that pressurized your avbay, but fell short of a CATO.
View attachment 438658
Was this a CTI motor? The 54s are known to blow-by the fwd o-ring, and it seems that more and more reports of it happening with the 38s are becoming common place, too (I've had 2 happen last year myself before learning about gluing the fwd closure).
OK, that rules out CTI forward closure blow-by issues causing an ebay pressure spike for the early flight anomaly. I would think that in an AT motor, such a failure would otherwise be catastrophically kinetic based on the case design.Based on another post, it was a 54mm AT K540
Only if you planned it that way. Otherwise something wrong with your setup.. Drogue harness too short? No NC retention (shear pins)? Overaggressive drogue charge?
No shear pins and probably not tight enough. I ground tested shear pins with no luck just bent and pulled them.
If this indeed was the flight from the locked thread, then it was an AT K540 metalstorm. A 3 second burn, so the T+1.85sec anomaly doesn't line up with motor burnout.
Something happened. A blow-by puff seems unlikely. As does a premature - but weak - deployment charge. And I would think a string wind shear would weathercock the rocket.
So, I don't know. it's a curiosity.
Was the main sitting on a piston that could have suddenly shifted down under thrust?
I’m guessing you’re on the right track nose cone came off at drogue deployment. No shear pins and probably not tight enough. I ground tested shear pins with no luck just bent and pulled them. 1.1 charge drogue and main.
If this indeed was the flight from the locked thread, then it was an AT K540 metalstorm. A 3 second burn, so the T+1.85sec anomaly doesn't line up with motor burnout.
Something happened. A blow-by puff seems unlikely. As does a premature - but weak - deployment charge. And I would think a string wind shear would weathercock the rocket.
So, I don't know. it's a curiosity.
Was the main sitting on a piston that could have suddenly shifted down under thrust?
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