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So Jeff Bezos has recently travelled to space aboard an Amazon-funded rocket, which has an unusual, egg-shaped nose.

Bezos' rocket, with egg-shaped nose

However, just about every other rocket I've seen has more of a cone-shaped nose, coming to more of a point. Here's an example, the Saturn V rocket:

Saturn V rocket with cone-shaped nose

I'd always assumed that the more straight-edged cone-shaped nose had been found to have the most favourable aerodynamics for a rocket to take flight.

Has this assumption now been proven wrong and an egg-shape offers less air resistance? or is there some other reason for this choice of design?

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    $\begingroup$ Are your examples meant to show that most rockets have cone shaped tips? The falcon rocket picture looks egg shaped at the top. The orbiter part of the space shuttle doesn't have a tip which comes to a sharp point. The solid boosters appear to have spherical nose tip. The examples, IMO, show the variety in the tips. $\endgroup$
    – AJN
    Jul 21 at 11:58
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    $\begingroup$ @user40799 This is getting off-topic, but what part of Bezo's statement "I also want to thank every Amazon employee and every Amazon customer because you guys paid for all of this" did you not understand? $\endgroup$ Jul 21 at 14:26
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    $\begingroup$ @DavidHammen - Bezos taking his assets based on founding Amazon and using them for his space company is different from Amazon paying directly. ] $\endgroup$
    – Jon Custer
    Jul 21 at 14:34
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    $\begingroup$ by that reasoning SpaceX is ebay funded. @DavidHammen $\endgroup$
    – user40799
    Jul 21 at 15:16
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    $\begingroup$ FWIW: A conical surface has zero Gaussian curvature. That makes it easy to fabricate cone shapes from flat material such as sheet aluminum. Curved surfaces like the dome-shaped nose of the New Shepard capsule are more expensive. I don't know what the New Shepard is made of, but the relative cost of curved vs. flat surfaces is much less with modern composite materials than it used to be with classic, metal "skin and stringer" airframe designs. $\endgroup$ Jul 21 at 17:46
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  1. Rocket noses come in all sorts and sizes. The driving factor is more likely to be functional than purely aerodynamic.
    For example, the shown Saturn V has a pointy nose, because that nose is wearing a pointy Launch Escape System.
    The Falcon 9 fairing nose is a blunted cone. (no escape system)
    The Falcon 9 hoisting a crew Dragon2 has a mostly-cone with a rounded nose. (escape system mounted on the sides, which is part of why it's not a smooth cone shape)
    The Soyuz nose is pointy, because like the Saturn V it has a very pointy launch escape system.
    In the case of BO's New Shepard, it has a launch escape system, but the motor is affixed to the capsule bottom, between it and the rocket body. Thus it does not affect the shape of the nose.

  2. If you are asking what shape is most aerodynamic, it would be a very sharp cone with a pointy tip. This shape is ok at subsonic speeds, and very superior at super->hypersonic speeds. Superior for drag, that is. It also heat up much more, and thus requires really fancy materials at the sort of speed rockets reach while still in real atmosphere.
    However, for a rocket mass is more important. The very small aerodynamic advantage a pointy tip confers is outweighed by the mass saving benefit of a blunted cone. That shape has much smaller surface area and is a naturally stronger shape, thus can be built using lighter materials.

Yes, BO's New Shepard's nose is quite sufficiently aerodynamic. It is also a very good shape to facilitate reentry, house the parachutes, and give the passengers a decent window view. As with most engineering designs, it is the balance of all the requirements that leads to a suitable compromise solution. Remember also that the New Shepard does not get to go very fast, it's top speed on the way up is only about 1000m/s, or mach 2.9-ish. Actual orbital rockets reach three times that speed in atmosphere on the way up, and 8 times that speed coming down.

What is not so aerodynamic is that ridge/ledge under the tip, where it joins the shaft. But this is required for the separation of the booster, and subsequent return of both pieces.

Supplemental info, specially added for jamesqf

THIS is a symmetrical aerofoil shape. Also known as "streamlined body"
(Airflow from the right to left. )
It is very aerodynamic. CD as low as 0.04
symmetric aerofoil, snatched from https://aviation.stackexchange.com/questions/39146/how-do-symmetrical-airfoils-generate-lift


THIS is the shape of a raindrop.
It is very non-aerodynamic, CD from 0.5 (very small droplets, almost spherical, image B below) up to 1.45. Yes, you read that right. One point four five, for a large raindrop about to break up under its own aero drag, image E below.
(Airflow from bottom to top)
Acual shapes of raindrops as function of size, from https://en.wikipedia.org/wiki/Drop_(liquid)


And the aerodynamic shape of the New Shepard is roughly a match for the rightmost of these shape, called the "bullet", which is basically a hemisphere on top of a long cylinder.
It is a pretty good but not perfect aerodynamic shape,
with a subsonic coefficient of drag of about 0.3 (due to the discontinuity leading to the rocket body)

(Airflow from left to right in this image)

Shape effect on subsonic air drag, from https://www.grc.nasa.gov/www/k-12/airplane/shaped.html

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    $\begingroup$ @jamesqf "A raindrop is most aerodynamic" is false. A raindrop is an incredibly high drag object. Are you maybe forgetting that a falling raindrop looks like a beanbag that uncle albert is sitting on? $\endgroup$
    – PcMan
    Jul 22 at 6:12
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    $\begingroup$ Actual shape of raindrops: scienceabc.com/pure-sciences/… or for image only scienceabc.com/wp-content/uploads/2016/06/… $\endgroup$
    – PcMan
    Jul 22 at 6:19
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    $\begingroup$ @jamesqf additionally, "a pointy cone with a sharp tip is quite un-aerodynamic at subsonic speeds. In fact, it would be more aerodynamic if you turned it around" is very false. Flat-based pointy cone with nose into the wind has CD of 0.34, same cone turned around has CD of 1.14 $\endgroup$
    – PcMan
    Jul 22 at 6:23
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    $\begingroup$ You're all really missing the point here, which is that aerodynamics on launch is fr from the primary consideration for shape. If you take for instance the Saturn V, the tip is pointy because that's the way they built the launch escape system. Then the Apollo CM is the size and shape it is because it had to hold three astronauts and have a re-entry heat shield. The SM/LM package fits nicely behind it. Then you have three stages that are basically soda can shapes, because that's how you minimize structure weight while maximizing propellant load. $\endgroup$
    – jamesqf
    Jul 22 at 16:15
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    $\begingroup$ @jamesqf Isn't that exactly what my answer says in the first place? Which point you tied to muddy by making multiple false statements in comments? $\endgroup$
    – PcMan
    Jul 22 at 16:25
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I'd always assumed that the more straight-edged cone-shaped nose had been found to have the most favourable aerodynamics for a rocket to take flight.

There's a key problem with sharp-nosed tips: They have a tendency to melt at high speeds. The Concorde only flew at Mach 2, and it's tip heated to 127 °C. This heating is a huge problem for hypersonic aircraft. This heating around sharp edges was part of why the Space Shuttle Columbia experienced its disastrous failure.

Modern launch vehicles don't have the pointy tips that the Saturn V and other early launch vehicles had. The pointy tip doesn't buy much with regard to aerodynamic efficiency, and it adds lots of risk.

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  • $\begingroup$ +1 Very interesting. $\endgroup$
    – copper.hat
    Jul 23 at 23:13
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In Joe Rogan #1609, Elon mentioned it makes no difference when it comes to rockets. It is arguable worse to be pointy.

As Antzi mentions, this is because of the speeds involved, and the issues with hypersonic flows.

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    $\begingroup$ In subsonic flows, the pointiness serves to move the air around. In hypersonic flows this can’t happen so it doesn’t matter much. You are right $\endgroup$
    – Antzi
    Jul 22 at 19:13
  • $\begingroup$ What's Joe Rogan 1609? And giving someone else's comment a thumbs up isn't much of an answer. Bottom line, this answer is pretty useless. $\endgroup$ Jul 25 at 0:19
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Boeing and SpaceX also use blunt nose cones (as demonstrated in these images), and not just for human capsules. Thus, unless all these engineers are incompetent, blunt cones must be a good idea.

enter image description here enter image description here

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    $\begingroup$ @DavidHammen what does "lack of accessibility" mean in this context? $\endgroup$
    – RonJohn
    Jul 24 at 11:59
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    $\begingroup$ @RonJohn Alt text can make an image-based answer comprehensible to those who are visually impaired. As is, this answer is useless to those who are visually impaired. Keep in mind the phrase "a good picture is worth 1000 words". This is not the case for the visually impaired. A nice description is essential. It doesn't have to be 1000 words long, but it is essential. $\endgroup$ Jul 24 at 22:04
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    $\begingroup$ I'm picking on you because this answer is one of the least accessible answers I've seen. You are not the only one who I've picked on for lack of accessibility. Accessibility is a touchy issue for me. I was exposed to the problem because I've had the privilege of working on multiple projects with a brilliant NASA mathematician who is totally blind. He's employed because he's brilliant. More than half of the visually impaired are not employed, and the problem is getting worse because of a growing over-reliance on imagery on the internet. $\endgroup$ Jul 24 at 22:11
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    $\begingroup$ @DavidHammen I hovered my mouse over every other image in teh question, and all the other answers, but saw no alt text. $\endgroup$
    – RonJohn
    Jul 24 at 22:11
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    $\begingroup$ @RonJohn Why should I enter image description? A halfway decent screen reader will access the image description. $\endgroup$ Jul 24 at 22:36

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