RE: Univ. of Illinois- TEDP 4 June 2013 Flight Week - Structural Review

[Danylo]

I'm sorry if I was unclear. We still plan to adjust the strap configuration as we discussed in the previous email. The calculations will be done for the new configuration which you recommended. At the moment we are just unsure of how to apply the calculation in the pdf that was sent to Sunny to our specific geometry.

Best,

Danylo

From my Android phone on T-Mobile. The first nationwide 4G network.

"ROE, ROBERT M. (JSC-CC311)" <robert...@nasa.gov> wrote:
Danylo,

Does this mean that Sunny is not going to change the securing method to straps and update the TEDP?  If not,  I'm not sure what calculations you would do, as I have received pretty good pictures already, so I'm not sure what else there is to see.  If you're unsure of the calculations required and don't believe there to be any shear, then we should plan on doing a pull test.  That will eliminate any ambiguity.  We would need to agree on how much to pull on your structure and where to do the pulling.  Because if it fails, I want to make sure there aren't any questions about how we loaded it up.

Bobby
________________________________________
From: Danylo Hirnyj [dhi...@gmail.com]
Sent: Sunday, May 19, 2013 12:33 AM
To: ROE, ROBERT M. (JSC-CC311)
Cc: moon...@googlegroups.com; Flint, Alan (JSC-CC311); Hickey, Alyson (JSC-CC311)
Subject: Re: Univ. of Illinois- TEDP 4 June 2013 Flight Week - Structural Review

Hello Bobby,

I was looking through the PDF that was sent to Sunny and it seems that the example is looking at a sheer situation which is not present in our experiment. The example requires loads along the edges in the plane of the Lexan sheet in opposite directions. To me, It seems that only a compressive loading on the Lexan needs analysis.

Sorry for the confusion, it is probably our fault for not adding more explicit documentation. Since we are getting ready to ship it, I suggest that we look at this in person, after which I can add the calculations required and get it back to you during one of the first days of flight week. We can also do a load test if necessary.

Best,
Danylo


On Mon, May 13, 2013 at 9:47 AM, ROE, ROBERT M. (JSC-CC311) <robert...@nasa.gov<mailto:robert...@nasa.gov>> wrote:
Danylo,

Thanks for the update.  My only confusion still is how the eye bolts are attached to the box.  Do they always go through part of the metal angles?  Also, the aft eye bolts, are they actually on the sides of the box?  I’m confused on which side is going to be the bottom and which side has the door, as well.  If you could give me a call, I have some questions for you about your box, and it  would be faster to talk than email back and forth on it.  My number is 281.244.9813<tel:281.244.9813>.

Thanks.
Bobby

From: Danylo Hirnyj [mailto:dhi...@gmail.com<mailto:dhi...@gmail.com>]
Sent: Saturday, May 11, 2013 8:46 PM
To: ROE, ROBERT M. (JSC-CC311); moon...@googlegroups.com<mailto:moon...@googlegroups.com>
Cc: Flint, Alan (JSC-CC311); Hickey, Alyson (JSC-CC311)
Subject: Re: Univ. of Illinois- TEDP 4 June 2013 Flight Week - Structural Review

Hello Bobby,
Again sorry for the delay. Most of us are graduating and have been swamped these last few weeks. Here is an updated version of the stress analysis which addresses the specific questions you asked. There is not highlighting because one section is almost entirely re-written with figures re-drawn. A change page has been added which clearly explains what changes have been made.
Thanks,
Danylo Hirnyj

On Tue, Apr 30, 2013 at 9:58 AM, ROE, ROBERT M. (JSC-CC311) <robert...@nasa.gov<mailto:robert...@nasa.gov>> wrote:
Danylo,

I’ve been asked to review your experiment for the upcoming reduced gravity flight week.  After reviewing your TEDP, I have the following questions/comments that I’m hoping you can clear up for me.


1.       I’m concerned about the strap attachment to the box with the eyebolt.  I would like to see the calculations that show this joint is sufficient.  Actual photos of this joint would help me follow your math as well.

2.       What orientation is the box in the aircraft?  I’m trying to figure out how the straps are actually arranged over the top of the box.  Because in a 9-g forward loading, the straps over the top of the box are going to be loaded due to the overturning moment.

Please do not submit any revisions of your TEDP to the RGO office except the last one after I have approved it.  When you submit an updated TEDP to me, please do the following:

*   Highlight text, track changes, show change bars, or provide some other method for denoting what changes have been made to the TEDP from the previous revision.
*   Update the change page and revision to reflect the update.

To ensure that everyone CC’d receives your response, REPLY ALL to this and all subsequent emails.

Please have a response to me within a week if possible.

Thanks,
Bobby Roe
NASA/JSC Aircraft Operations
281.244.9813<tel:281.244.9813>

[Danylo Hirnyj]

---------- Forwarded message ----------
From: Danylo Hirnyj <dhi...@gmail.com>
Date: Fri, May 31, 2013 at 11:23 PM
Subject: Re: Univ. of Illinois- TEDP 4 June 2013 Flight Week - Structural Review

To: "ROE, ROBERT M. (JSC-CC311)" <robert...@nasa.gov>
Cc: "Hickey, Alyson (JSC-CC311)" <alyson....@nasa.gov>, "Flint, Alan (JSC-CC311)" <alan.n...@nasa.gov>

Hello Bobby,

Here are the changes which we discussed today. This includes everything that you requested. It seems that this new strap configuration is much more robust!

I understand that you are busy this weekend. Once you have a chance to look this over, please let me know asap if anything else is needed.

Best,
Danylo Hirnyj

On Wed, May 29, 2013 at 1:47 PM, ROE, ROBERT M. (JSC-CC311) <robert...@nasa.gov> wrote:

Danylo,

 

The only calculations I’m looking for at this time, from what I know of your box, is the strap calculations and then the compressive beam buckling of the vertical metal angles in the corners.   For the strap calculations, the floor allowable is 2500 lbs in any direction of pulling on the floor ring.  The strap can take 5000 lbs, so you don’t need to worry about it.  You need to scetch up where you are going to attach straps on your box and show where on the floor each strap will go.  Then you need to do the math based on the 9g forward crash condition to show that the loads felt in the straps don’t put more than 1250 (2500 divided by a safety factor of 2) lbs on any one floor ring.  Remember the rings are spaced on a 20”x20” grid on the floor.  All of this information can be found in AOD document 33897 and the Zero-g Interface control document (ZGC-lCD).   As for the beam buckling, you’ll just find the downforce put in the vertical angle in the aft two corners from the strap during a 9g fwd crash and see if they are strong enough to take that downward compressive buckling load.

 

If this doesn’t make sense, then if you think a phone call can clear it up, by all means, call me at 281.244.9813.  Otherwise, yes, we can go over it in person.  I will be here this Thursday and Friday, but not Monday during loading.  However, I’m not going to do all of the calculations for you, I will just get you started, so it will be up to you to do it right and then I’ll review it and have you make any changes that are necessary.   This method wouldn’t assure you flying Tuesday as I don’t know how long it’ll take you to do the calculations.  Just FYI.

 

Thanks, Bobby

 

From: Danylo Hirnyj [mailto:dhi...@gmail.com]
Sent: Wednesday, May 29, 2013 1:37 PM

To: ROE, ROBERT M. (JSC-CC311)

Subject: Re: Univ. of Illinois- TEDP 4 June 2013 Flight Week - Structural Review

 

Hey Bobby,

I did not send it since I was unsure of how to do the calculations you were requesting. Would it be possible to go over this in person, and then get it back to you the same day?

Best wishes,
Danylo

 

On Wed, May 29, 2013 at 9:04 AM, ROE, ROBERT M. (JSC-CC311) <robert...@nasa.gov> wrote:

Danylo,

Have you sent me your updated TEDP with the new strapping plan yet?  If so, I think I've misplaced it, can you send me it again.  I believe that was the only outstanding issues left before flight.

Bobby

________________________________________

From: ROE, ROBERT M. (JSC-CC311)

Sent: Monday, May 20, 2013 9:39 AM
To: Danylo

Cc: moon...@googlegroups.com; Flint, Alan (JSC-CC311); Hickey, Alyson (JSC-CC311); Del Rosso, Dominic L. (JSC-CC411); Lee, Terry A. (JSC-CA211)
Subject: RE: Univ. of Illinois- TEDP 4 June 2013 Flight Week - Structural   Review

Dangle,

If you strap it from the top, then you're right the PDF equation doesn't apply.  It only applies with your original strapping configuration.  Glad your changing your strapping method, I'm pretty sure we won't have to do a load test then.

Bobby
________________________________________
From: Danylo [dhi...@gmail.com]
Sent: Sunday, May 19, 2013 9:47 PM

To: ROE, ROBERT M. (JSC-CC311)

Cc: moon...@googlegroups.com; Flint, Alan (JSC-CC311); Hickey, Alyson (JSC-CC311); Del Rosso, Dominic L. (JSC-CC411); Lee, Terry A. (JSC-CA211)
Subject: RE: Univ. of Illinois- TEDP 4 June 2013 Flight Week - Structural   Review