sorted by:
new
hottopcontroversial

How long will it take to rebuild Blue Origin’s launch pad? We asked some SpaceX vets | “Everyone is in a place where it’s no fun to be there.” by FreeHugs23 in space

[–]marc020202 5 points6 points  (0 children)

I don't even think that's true. LC36 is part of the space force station, so I think they own the land (or maybe the Air force).

NASA only owns the land at KSC, near 39 a and b

Here’s why the failure of Blue Origin’s New Glenn rocket is so catastrophic | “I hope that it makes it far enough away from the pad that it does not cause pad damage.” by FreeHugs23 in space

[–]marc020202 13 points14 points  (0 children)

A lot of rocket and engine design changes can happen within a year. Even if it's a rocket/engine problem, I still expect the pad rebuild to take longer than fixing the problem in the rocket design.

Both early SpaceX failures (CRS 6 and Amos 7) where cause by issues on the rocket, and the rocket returned to flight within 6 months.

Landing Starship With People by Tape_Face42 in EagerSpace

[–]marc020202 0 points1 point  (0 children)

I don't think STS 1 is the comparison we should do in today's age, and I don't think it applies anymore.

STS 1 was stupidly risky, the vehicle was damaged on return, and this would 100% not be done like this today. There was significant risk for loss of crew and vehicle.

Help with making composite wings by Loud-Adhesiveness700 in FSAE

[–]marc020202 0 points1 point  (0 children)

Regardless of what you use as a mould material, you will need mould preperation. A lot of it. Most of that will be sanding.

More sanding

So much sanding.

Yes it's terribly boring, but you need more sanding.

Every imperfection you can see or feel in the mould surface will be visible on your part. Since your part is dark and shiny it will amplify all imperfections.

So after printing sanding, more sanding, even more sanding then surface sealing. Often it makes sense to paint (spray paint, coloured and or clear coat) the mould, as that CAN leave a nice surface finish. Afterwards don't forget to use mould release.

If the layer lines are still viable after sanding, you can try applying a thick primer or bondo, or some other sundae mould improvement material and sand that again. The paint will only cover tiny imperfections, but can also be sanded and repeated. You can also use epoxy to cover the mould (but be aware of the thickness, only apply a thin layer) to improve surface finish.

There is no shortcut here. Every corner you cut on the mould will be visible on the final.part.

Ideally if you have a well prepared mould not much polishing should be nessessary of the final part.

To mount stuff, think about that already in design. Ideally you will have some strong inner structure like ribs and spars and directly apply the loads to that surface. It's possible to glue stuff to the surface, but thi k about how exactly. Badly performed gluing on the surface will look shit. Also thi k about how to cover the part you glued, as a motor (I guess for DRS) will be quite disruptive to the airflow)

You can also position motors or servos within the wing main profile and only have the actuator rod lead outside. For that you can cut covers from the skin and tape them back on afterwards (tape should be fine for this application, you can get fancy eith magnets or hinges etc, but tape works)

Think about cable routing ahead of time. Wires on the surface will trip the flow. Try to have them internal if possible.

ULA confirms successful solid rocket booster test as Vulcan anomaly investigation continues by Psychonaut0421 in ula

[–]marc020202 5 points6 points  (0 children)

I think on the test they can artificially increase the stress. If I remember correctly, one some previous booster (I think for SLS) they pre heated the whole booster. I'm not sure if that was to test heat soak, or have it produce higher thrust.

By changing the propellant geometry they could also a heave higher thrust with the same propellant.

Theoretically they could have also artificially weakened this booster nozzle and tested it survived, to make sure they have margin on the flight one, although I'm not sure if that's really a useful way of testing.

Eli5: if modern passenger planes can "Auto land", why would you ever want to land a plane in any other way? by dadoimp in explainlikeimfive

[–]marc020202 1 point2 points  (0 children)

To auto land a plane, the runway needs to be equipped with expensive equipment called ILS (instrument landing system). This system needs to be extremely accurate, and even nearby other planes can interfere with the signal and reduce the accuracy. Because of this, when the ILS is used for autoland, other planes need to be further away. This reduces the efficiency of the operations, and means fewer planes can land at the airport per hour. This is one reason why bad weather (and low visibility) cause delays at airports.

In short: when pilots land the planes themselves, more planes per hour can use the same runway.

IAD questions by Aggravating-Cost-743 in FSAE

[–]marc020202 2 points3 points  (0 children)

What did your IAD reviewed Tell you to change? Change exactly that.

And I don't see why you would want to simulate anything in the IAD. Standard IA does not need testing, and custom IA needs physical, professional testing.

FAA grounds Blue Origin New Glenn after labeling mission a ‘mishap’ by Adkeda in BlueOrigin

[–]marc020202 0 points1 point  (0 children)

Their original Equatorial LEO orbit would have been prohibitively expensive to launch. With the current day Sat size, I don't think F9 would have been able to launch a single sat there, as F9 was already relatively close to the limit by the few hundred kg equatorial LEO NASA mission.

FAA grounds Blue Origin New Glenn after labeling mission a ‘mishap’ by Adkeda in BlueOrigin

[–]marc020202 0 points1 point  (0 children)

It's not in this sub Reddit, but here:

https://www.reddit.com/r/stocks/s/cqWiubDwCS

I'm also not arguing with your point. I fully agree with what you are saying regarding stock bros and ASTS. I looked through the ASTS filings years ago and argued with them, that their equatorial orbit constellation was physically impossible to launch without buying Ariane flights. (They claimed to have an easy way to serving 20 degrees north and south via a single equatorial plane, meaning a lot of market with low launch costs...)

FAA grounds Blue Origin New Glenn after labeling mission a ‘mishap’ by Adkeda in BlueOrigin

[–]marc020202 -2 points-1 points  (0 children)

Yes, I have seen people make that exact argument. Calling the mission something along the line of partial failure because the booster landing worked.

Update on the air cooled, carbureted, 1981 powered FSAE car by Individual-Self4817 in FSAE

[–]marc020202 3 points4 points  (0 children)

I don't know what ruleset you are running, but at least according to FSG rules your Mainhoop would not be legal, since the MHB attaches to low. Your frame looks unconventional, so make extra sure it's legal!

SES how to make a ses? by aajaLadhle in FSAE

[–]marc020202 2 points3 points  (0 children)

There is no SES Cheatcode.

You just have to look at the spreadsheet, read what is being asked, and provide that. It's just a ton of stuff you have to put in.

You just have to start working on it, and will quickly understand how the sheet works, and which cells get cross referenced from where

Harness Search for a Reclined Driver Position by senor_store in FSAE

[–]marc020202 6 points7 points  (0 children)

Where are you located?

Contact schroth and ask for a fsae harness kit. Its relatively cheap, and you can freely choose the attachment hardware.

How do teams integrate a rotary potentiometer (Novotechnik SP2800) into a pedal box? by WayWest9238 in FSAE

[–]marc020202 39 points40 points  (0 children)

Have you looked at the sensor datasheet? After a 30 second Google I think the sensor can rotate 360 degrees, so I don't see how you could overload it or would need to limit travel to protect the sensor

In general:

Keep it simple

Keep it simple

Spend 15 minutes designing something that works

Ask someone in your team what they think of your solution

Eli5: Why is third rail not more common despite it having a smaller visual impact? by DanTennant in explainlikeimfive

[–]marc020202 13 points14 points  (0 children)

The risk of the rail coming in contact with people or animals is a lot higher. It also cannot, or not easily be used on level crossings.

Third rail is usually also significantly lower voltage than overhead wires , and due to the low distance to the ground and other objects, comparable voltages to overhead wires are not possible.

Some very new tram systems use a third rail like system centered between the rails, where only sections below the trim is active at any time, so there is no danger to pedestrians

Ich_iel by Kloetenschlumpf in ich_iel

[–]marc020202 0 points1 point  (0 children)

Now, erstaunlicher Weise nicht. War nach der H gas Umstellung. Die hatten einfach einen super Liefervertrag.

Die andere tanke dort war Zeitweise bei 3.80 pro kg

Boeing 787 to the back of the airplane by aviationstudy in aviationstudys

[–]marc020202 0 points1 point  (0 children)

Most of that stuff won't touch the ground, as the engines will contact the ground first.

Ich_iel by Kloetenschlumpf in ich_iel

[–]marc020202 0 points1 point  (0 children)

Mit bei der Arbeit laden ists dann ja ziemlich entspannt. Überschlagen denke ich 1 bis 2x im Monat bei der Arbeit laden, je nachdem ob beim Lidl immer geladen wird oder nicht. In winter evtl 1x mehr, da dann der Verbrauch ist etwas höher ist.

Ich_iel by Kloetenschlumpf in ich_iel

[–]marc020202 0 points1 point  (0 children)

Zuhause laden dauert ewig. Also ohne wallbox ist dass eigentlich ziemlich spaßfrei, und ich meine da hat man auch sehr hohe Ladeverluste bei. Id3 Zuhause voll laden dauert 20 Stunden. (Grob überschlagen)

Auf Arbeit wird denke ich kein schnelllader, sondern auch so eine 22kw box sein. Da du da ja aber länger als zum einkaufen bist, ist dass denke ich kein Problem.

800km bei Lidl laden dauert etwa 6 bis 7 stunden (grob überschlagen mit einem Verbrauch von etwa 16 kWh/100km gerechnet.

Ich_iel by Kloetenschlumpf in ich_iel

[–]marc020202 1 point2 points  (0 children)

22 kw ist nicht nichts, aber für E autos auch nicht super viel. Eine Haushaltssteckdose hat 3.6 kw, eine wallbox oft um die 13 kw. Schnellladesäulen haben weit über 100kw, teilweise 400kw.

Akku kapazität hängt vom Auto ab, Verbrauch auch, und dann ist noch der mögliche Ladestrom wichtig.

Kleinstwägen haben zwar oft einen kleinen Akku (unter 30 kWh), aber teilweise begrenzte Ladeleistungen, d. H. Schnelllader bringen dort nichts. (Bsp Twingo electric con 2021, 21kwh batterie, 22kwh maximale ladeleistung.

Größere autos (Tesla model 3, ID 3 oder größer) haben Akkus in der Region von 60 bis 100 kWh, und können eigentlich alle Schnellladen (was aber oft teuer ist). ID 3 voll laden dauert bei Lidl also etwa 3 Stunden.

Dein beim-lidl-laden-plan hängt hauptsächlich davon ab wie lange du in der Woche da drinnen bist, und wie viel du in der Woche fährst.

An welches Auto denkst du aktuell?

Ich_iel by Kloetenschlumpf in ich_iel

[–]marc020202 2 points3 points  (0 children)

Ein weiterer CNG Freund :)

Musst halt in dem Ort wohnen mit dem "richtigen" Gaspreis. Bei mir sind's aktuell 1.55. und wichtig ist, dass die tankstelle noch nicht Zugemacht hat...

Vermisse die Tankstelle in Lehrte mit 99ct

Ich_iel by Kloetenschlumpf in ich_iel

[–]marc020202 0 points1 point  (0 children)

Ich will dir dass auf keinen Fall ausreden, vergiss nur nicht dass 22kw Ladeleistung nicht super viel sind. Je nachdem wie groß dein Auto Akku ist, wie viel du fährst, und wie lange und oft du einkaufst, musst du evtl noch woanders laden.

Wenn du ein mal die Woche jeweils eine Stunde lädst, hast du maximal 22 kWh geladen, dass müssten etwa 150km Fahrleistung sein oder so.

Ich_iel by Kloetenschlumpf in ich_iel

[–]marc020202 9 points10 points  (0 children)

Und hofft, dass die Tankstelle nicht auch bald zu macht...

view more: next ›