Why Did the SATURN V Have Fins ?

[Ez2cDave]

Why did the SATURN V have Fins ?

https://apollo11space.com/why-did-the-saturn-v-have-fins

Dave F.

 

[techrat]

It's funny you brought this up, because I was going to ask which rockets still have fins.... Sounding rockets are finned, but most launches we get to see these days such as from RocketLab or SpaceX, are finless, although it looks like Neutron is going to have fins which are really just built-in landing legs. Does Starship count as having fins, as those seem more like itty bitty wings, more like DreamChaser. But it does seem that most rockets these are days are sans-fins.

 

[Funkworks]

I like this photo from the link. Has anyone in here built a flying scale version of the Saturn escape scenario?

 

[Ez2cDave]

It's funny you brought this up, because I was going to ask which rockets still have fins.... Sounding rockets are finned, but most launches we get to see these days such as from RocketLab or SpaceX, are finless, although it looks like Neutron is going to have fins which are really just built-in landing legs. Does Starship count as having fins, as those seem more like itty bitty wings, more like DreamChaser. But it does seem that most rockets these are days are sans-fins.

Virtually all "finless rockets" have a guidance system to keep them on the intended flight path . . .

A notable exception are "missiles", which have both a guidance / tracking system ( or multiple systems ) AND have Fins. In the case of "missiles", however, at least one set of Fins are controlled by the guidance / tracking system(s) to either precisely strike a designated target or to pursue a "moving target", in order to strike it.

Sounding Rockets, for the most part, are "unguided" and require Fins, for stability.

Dave F.

 

[Cape Byron]

I like this photo from the link. Has anyone in here built a flying scale version of the Saturn escape scenario?

View attachment 585092

There have been a couple built - I seem to remember @Gus was involved with one.

Boyce also have a single motor builders kit if you don't want to go the scratch built route:

boyceaerospacehobbies.com/products/apollo-abort-capsule-kit-24mm?_pos=1&_sid=2218a5621&_ss=r

 

[Gus]

I like this photo from the link. Has anyone in here built a flying scale version of the Saturn escape scenario?

View attachment 585092

My Pad Abort model flying at the World Spacemodeling Championship in Slovakia in 2012:

Thread here on TRF about building working Pad Abort models.

https://www.rocketryforum.com/threads/apollo-capsule-pad-abort-test-vehicle.95119/page-5

Youtube video about the Pad Abort model project:

 

[Gus]

A couple more photos of my Pad Abort.

With Walt Cunningham of Apollo 7 at NARAM years ago. When asked if he ever thought about what it would be like to ride an actual abort he replied, "no, we just figured it would be better than being on top of an exploding Saturn V." LOL.


My Pad abort flying at the Apollo 11 memorial demonstration at TARC in 2019.Thanks to Jim Wilkerson of Tahoma Photography for the great photo.

 

[Ez2cDave]

When asked if he ever thought it would be like to ride an actual abort he replied, "no, we just figured it would be better than being on top of an exploding Saturn V."

Words to live by . . . Literally !

Very cool model . . .

Dave F,

 

[Sooner Boomer]

Why did the SATURN V have Fins ?

https://apollo11space.com/why-did-the-saturn-v-have-fins

Dave F.

The answer from the web site is "for emergencies". They claim that the fins provide drag to slow down the rocket in case the capsule emergency system were fired. There are other reasons. 1) the fins help cover part of the engine mounting structure. 2) the fins provide mounting structure and aerodynamic cover for the 1st stage retrorockets. There are two retrorockets in each fin.

Engine mounting:

https://upload.wikimedia.org/wikipedia/commons/7/7e/Ap10-KSC-68C-7912.jpg

Separation and retrorockets (about half-way down page) -

Rocket Propulsion Evolution: 8.10 - S-IC Stage

 

[Ez2cDave]

 

[lakeroadster]

I'm old enough to remember when all inter-office mail was placed in envelopes similar to the one shown above.... we all had "in-boxes" and "out-boxes". And the "Mail Boy" (also known as the "Print Boy") would come around twice a day to collect and distribute.

You weren't being inundated with emails that distracted you all day long.

Good times.

 

[Buster]

Why did the SATURN V have Fins ?

https://apollo11space.com/why-did-the-saturn-v-have-fins

Dave F.

Because Werner said “A rocket must have fins!”

 

[tfrielin]

Because Werner said “A rocket must have fins!”

Exactly---what I've always heard as the reason.

He thought it gave the abort system a couple of three seconds longer to activate as the fins would provide stability for that long if things went bad.

Except his Saturn I didn't have fins for the first several flights. Go figure...

 

[lakeroadster]

Exactly---what I've always heard as the reason.

He thought it gave the abort system a couple of three seconds longer to activate as the fins would provide stability for that long if things went bad.

Except his Saturn I didn't have fins for the first several flights. Go figure...

Ya didn't click on the link that @Ez2cDave provided in the 1st post... did ya?

... "The fins are there for emergencies, not normal flight. The fins’ purpose is to extend the period that the astronauts have to trigger their escape rocket LES, (Launch Escape System), before the break up of Saturn V." ...​

 

[tfrielin]

Ya didn't click on the link that @Ez2cDave provided in the 1st post... did ya?

... "The fins are there for emergencies, not normal flight. The fins’ purpose is to extend the period that the astronauts have to trigger their escape rocket LES, (Launch Escape System), before the break up of Saturn V." ...​

Obviously not----But, still I'm glad I got the answer right!

 

[tfrielin]

Obviously not----But, still I'm glad I got the answer right!

Re the fins---It's also interesting to note that had a second batch of Saturn Vs been manufactured beyond the original fifteen, in addition to upgrading it with the F-1A and J-2S engines, the fins likely would have been removed.

They weren't simple, single piece construction, but made of many parts. Eliminating the fins, and thus reduciing thr parts count would have worked to lower the cost.

It's realy a shame we scrapped the Saturn V (and the IB) for false promise of the Shuttle.

Over fifty years later and over a decade since the Shuttle was retired, we are trying to re-create the lost capability of Saturn/Apollo hardware, not the Shuttle.

What does that tell you??

 

[lakeroadster]

Re the fins---It's also interesting to note that had a second batch of Saturn Vs been manufactured beyond the original fifteen, in addition to upgrading it with the F-1A and J-2S engines, the fins likely would have been removed.

They weren't simple, single piece construction, but made of many parts. Eliminating the fins, and thus reduciing thr parts count would have worked to lower the cost.

It's realy a shame we scrapped the Saturn V (and the IB) for false promise of the Shuttle.

Over fifty years later and over a decade since the Shuttle was retired, we are trying to re-create the lost capability of Saturn/Apollo hardware, not the Shuttle.

What does that tell you??

It tells me that NASA changes focus based on the whims of the latest elected party in power.

 

[tfrielin]

It tells me that NASA changes focus based on the whims of the latest elected party in power.

And bi-partisan pork barrell politics.

 

[Ez2cDave]

Re the fins---It's also interesting to note that had a second batch of Saturn Vs been manufactured beyond the original fifteen, in addition to upgrading it with the F-1A and J-2S engines, the fins likely would have been removed.

They weren't simple, single piece construction, but made of many parts. Eliminating the fins, and thus reducing the parts count would have worked to lower the cost.

Speaking of SATURN V fins . . .

 

[Lord Rory Gin]

Re the fins---It's also interesting to note that had a second batch of Saturn Vs been manufactured beyond the original fifteen, in addition to upgrading it with the F-1A and J-2S engines, the fins likely would have been removed.

They weren't simple, single piece construction, but made of many parts. Eliminating the fins, and thus reduciing thr parts count would have worked to lower the cost.

It's realy a shame we scrapped the Saturn V (and the IB) for false promise of the Shuttle.

Over fifty years later and over a decade since the Shuttle was retired, we are trying to re-create the lost capability of Saturn/Apollo hardware, not the Shuttle.

What does that tell you??

At the time of the shuttle they told another story. They said that if it weren't for Kennedy's mandate of putting man on the moon, they could have continued on with the X-15 and the space plane program and created the shuttle and space station by the end of the '60s. That's the direction Von Braun and his team were wanting to go. So I guess its a matter of perspective as to which program interrupted which.

 

[Ez2cDave]

Why Has It Been 50 Years Since Humans Went to the Moon ?

https://airandspace.si.edu/stories/editorial/why-50-years-since-humans-went-moon

 

[Art Upton]

X-20 shuttle and the MOL space station was canceled by McNamara before any thoughts on the shuttle was made in the 60s.

Reason Blue Gemini was canceled? Our Spy Sats made them not needed.

Then when the original Shuttle on top of the stack was moved so the crew was at the bottom of the stack, that was just bad news and also while tiles were always stripped away on launches.

It was so weird, in the early days of the flying program they had Tile Repair kits an EVA was to be done to fix a tile like using Bondo on a car.

Tiles were made by John's Mansville at a plant near me at one time.

 

[Ez2cDave]

 

[Art Upton]

I always do not believe official statements on such things. I simply say ok maybe or maybe not

 

[Art Upton]

The original Shuttle , at the top of the stack did not need Tiles for reentry. Both moving it to the bottom of the stack and the use of Tiles was done as budget cuts in the late 70s [I wont say by who to avoid politics]

 

[Ez2cDave]

 

[Art Upton]

Me, and my Wife saw that stack at that year visiting on Vacation. She said something was going to go wrong. Yep it got shut down at T -3 due to a top of the tank leak. They fixed it after a few days and it launched.

The last flight of that named shuttle had the same thing happen, leak at the top of the tank. They said "we know how to fix this now" and it got fixed and launched a little while later.

 

[tfrielin]

At the time of the shuttle they told another story. They said that if it weren't for Kennedy's mandate of putting man on the moon, they could have continued on with the X-15 and the space plane program and created the shuttle and space station by the end of the '60s. That's the direction Von Braun and his team were wanting to go. So I guess its a matter of perspective as to which program in...

A plausible evolution scenario.

But in reading more recent space history---and given the reality that WE DID develop Saturn/Apollo---it is clear that the Shuttle decision was a mistake that took us on a forty, fifty year detour from which we are still trying to recover.

See John Logsdon's After Apollo (2015) in which he relates what I call NASA's Critical Moment:

In August, 1971, George Low was having last minute doubts as to whether NASA should keep pushing the Administration for Shuttle approval and instead propose an alternate manned program consisting of a more permanent space station (a follow-on to Skylab) and, later, a manned lunar base.

Had Low and NASA gone that route, it would have required keeping the Saturn/Apollo infrastucture (Saturn V production was halted in August, 1968---by LBJ's Administration. But NASA retained the tooling until late 1972---just in case).

Nixon is everyone's favorite space villian---"He killed Apollo because he hated Kennedy" is the short version.

But in reality, he said he wouldn't countenence the end of the US manned spaceflight program on his watch. He just didn't want to spend at the crash program levels of the '60s and just wanted NASA to present him with an affordable program.

NASA blew it with the Shuttle which as we know turend out not to be cheap or routine. Reusable, yes, but not cheap. Or routine.

Again, all this is in Logsdon's After Apollo---very interesting reading.

Anyway---back to those fins...