New engines weaker than old?

New engines weaker than old?

Post by Roy Gre » Thu, 19 Dec 1996 04:00:00



Quote:

>Is it just me, or are the new Estes engines not up to the same power as
>the old.  I quit building rockets 10 years ago, but just started again
>with my son.  I fly at the same field and even fly some of the same
>models.

>That new C-6-5 just doesn't seem to get it quite like the old ones.  I
>used to be afraid of that engine, because I lost too many rockets.  Now it
>just seems to push them barely above the tree tops.  We used to use the
>alti-trac, so I know it can't just be aging memories.

>Any thoughts????

>Bill

No, you're probably just bigger, and older, with a bit different
perception of space and time.

When i flew my first rocket in 1968, an Alpha with an A8-3, i thought
it went at least a thousand feet... way up there in any case.  now an
Alpha with an A8-3 seems to be merely a lob.  but it's the same rocket
with the same motor.   The only difference is I'm a foot or so taller
and 50 pounds heavier.

 
 
 

New engines weaker than old?

Post by Danger w » Thu, 19 Dec 1996 04:00:00


Is it just me, or are the new Estes engines not up to the same power as
the old.  I quit building rockets 10 years ago, but just started again
with my son.  I fly at the same field and even fly some of the same
models.

That new C-6-5 just doesn't seem to get it quite like the old ones.  I
used to be afraid of that engine, because I lost too many rockets.  Now it
just seems to push them barely above the tree tops.  We used to use the
alti-trac, so I know it can't just be aging memories.

Any thoughts????

Bill

 
 
 

New engines weaker than old?

Post by The Silent Observe » Thu, 19 Dec 1996 04:00:00


Quote:

> Is it just me, or are the new Estes engines not up to the same power as
> the old.  I quit building rockets 10 years ago, but just started again
> with my son.  I fly at the same field and even fly some of the same
> models.

> That new C-6-5 just doesn't seem to get it quite like the old ones.  I
> used to be afraid of that engine, because I lost too many rockets.  Now it
> just seems to push them barely above the tree tops.  We used to use the
> alti-trac, so I know it can't just be aging memories.

> Any thoughts????

Despite your Alti-trac, it's probably just a change in perceptions.  A
Big Bertha was a >huge< model when I was 13 years old and in 8th grade.  
It flew poorly on A, well on B, and very, very high on a C motor.

Now, I find the B flights pretty wimpy (a couple hundred feet) and the C
flights nice; a D21 is >really< fun and my new Bertha is getting a 24mm
mount so I can fly on the cheaper D12 motors as well as the E15.

I remember the flame and roar from a D motor as being in the Saturn class
in 1973, too...now, they seem pretty tame, especially after being around
a few H, I, J, and even K launches...

--
+----------------------------------------------------------------------+
| There are two kinds of fool.  One says, this is old, and therefore   |
| good, and one says, this is new, and therefore better.               |
|                                  John Brunner, _The Shockwave Rider_ |
+----------------------------------------------------------------------+

| Rocket Pages           http://members.aol.com/silntobsvr/modrocs.htm |
+----------------------------------------------------------------------+
| All opinions expressed are my own, and should in no way be mistaken  |
| for those of anyone but a rabid libertarian.                         |
+----------------------------------------------------------------------+

 
 
 

New engines weaker than old?

Post by pauldim.. » Mon, 23 Dec 1996 04:00:00



Quote:

>That new C-6-5 just doesn't seem to get it quite like the old ones.  I
>used to be afraid of that engine, because I lost too many rockets.  Now
it
>just seems to push them barely above the tree tops.  We used to use the
>alti-trac, so I know it can't just be aging memories.

>Any thoughts????

I agree with others that the engines of the same description (C6-5)
perform the same as they always have.  Probably minor differences
regarding quality perhaps... But the rating system serves the purpose of
stating the performance of the engines.  The engine has to perform at that
level to be called a C6-5.  

I do believe though that when I see things now that I last saw as a kid,
just don't seem as big, not as fast, not as kool, simply not like they
were.   Oh well!!!

Paul.

Fly Baby Fly!

 
 
 

New engines weaker than old?

Post by Eric32 » Tue, 24 Dec 1996 04:00:00


Quote:

>That new C-6-5 just doesn't seem to get it quite like the old ones.  I
>used to be afraid of that engine, because I lost too many rockets.  Now
it
>just seems to push them barely above the tree tops.  We used to use the
>alti-trac, so I know it can't just be aging memories.

>Any thoughts????

  I remember talking to an NAR old timer a few years ago at a competition
meet. He used some archaic Estes motors because he claimed they were more
powerful. He said they were a full 10 Ns. The current Estes C6 motors test
out as 9 Ns according to NAR S&T. So there might be a little more than
exaggerated memories going on here, but it is not likely that a 10%
decrease in total impulse would produce anything other than a small
reduction in altitude. Probably a little bit of both going on.
 
 
 

New engines weaker than old?

Post by Roy Gre » Tue, 24 Dec 1996 04:00:00


Quote:


>>That new C-6-5 just doesn't seem to get it quite like the old ones.  I
>>used to be afraid of that engine, because I lost too many rockets.  Now
>it
>>just seems to push them barely above the tree tops.  We used to use the
>>alti-trac, so I know it can't just be aging memories.

>>Any thoughts????
>  I remember talking to an NAR old timer a few years ago at a competition
>meet. He used some archaic Estes motors because he claimed they were more
>powerful. He said they were a full 10 Ns. The current Estes C6 motors test
>out as 9 Ns according to NAR S&T.

There's a MIT Rocket Society report from the mid 70's that debunks
that theory, showing Estes, Centuri, FSI, and MRC/AVI motors tested at
around the levels for normal certification.  i.e. the mean total
impulse being under the max enough that only a small percentage might
go over.  I think two Std. Deviations?  

For a C6-5 or -7 there *might* be a possible reason that one year's
production run might be stronger or weaker than the previous or next
year's and that is the quality of the black powder that Estes was able
to get.  since the C6, A3, and D12 are designed at the maximum of what
can be put in a casing, it may be possible that a weaker batch of BP
had to be adjusted in order to fit in the casing.

Quote:
> So there might be a little more than
>exaggerated memories going on here, but it is not likely that a 10%
>decrease in total impulse would produce anything other than a small
>reduction in altitude. Probably a little bit of both going on.

very slim chance that the average C6 motor of 1996 performs
significantly different from a C6 of 1986 or 1976 or 1970.