Author Topic: New 109's  (Read 3148 times)

Offline LRRP22

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« Reply #15 on: October 11, 2005, 03:50:32 PM »
Quote
Originally posted by Porta
Mustang's racks are Mustang's racks, and 109's gondolas are 109's gondolas ...

The speed loss was measured consistently to be 9-12 km/h (at 0 m and ~500 km/h).


Ah, that's probably the reason- 9 kph at 500kph for the 109, while the Mustang's 12 kph loss at SL was measured between 600 (USAAF) and 640 (RAF) kph.



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Offline Krusty

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« Reply #16 on: October 11, 2005, 05:07:38 PM »
Well DUH the P51s bomb racks are going to make more drag. They're BOMB racks, with shackles and mounting slots and all that fun stuff, none of which (I might add) is conducive to aerodynamic flow.

Gun pods, on the other hand, only have the ejection chute (and the barrel of the gun itself is probably negligable drag).

Offline LRRP22

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« Reply #17 on: October 11, 2005, 06:11:23 PM »
Quote
Originally posted by Krusty
Well DUH the P51s bomb racks are going to make more drag. They're BOMB racks, with shackles and mounting slots and all that fun stuff, none of which (I might add) is conducive to aerodynamic flow.

Gun pods, on the other hand, only have the ejection chute (and the barrel of the gun itself is probably negligable drag).



Have you ever actually looked at a P-51's wing racks?  





Not exactly the draggiest appendage imaginable, is it?







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« Last Edit: October 11, 2005, 06:33:14 PM by LRRP22 »

Offline LRRP22

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« Reply #18 on: October 11, 2005, 06:25:04 PM »
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« Last Edit: October 11, 2005, 06:33:42 PM by LRRP22 »

Offline Crumpp

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« Reply #19 on: October 11, 2005, 09:00:05 PM »
Quote
Not exactly the draggiest appendage imaginable, is it?


It looks like a typical WWII wingmounted rack.  Absolutely nothing special.

Reminds me of larger version of the ETC 50 rack.

Quote
The deal with the 190a5 was that the pylon wasn't counted towards drag, even after the centerline ord was dropped. I think on the 109s that the gondies have always been counted. No change, is my guess.


Is the ETC 501 rack always mounted on the FW190 in AH?  It should not be as it was removed and replaced as mission required.

The Flugzeug-handbuch specifies it will be removed if not in use.

Having no experience and no manual it took a couple of guys about 4 hours to remove our ETC rack.  However an experienced crew of 4 could do it in about 15 minutes.  Surprisingly it is one of the more involved FW190 maintenance tasks.

All the best,

Crumpp

Offline Krusty

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« Reply #20 on: October 11, 2005, 09:24:51 PM »
Crumpp, the rack is not there if nothing is loaded.

Offline Crumpp

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« Reply #21 on: October 11, 2005, 09:36:31 PM »
Thanks.

Offline LRRP22

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« Reply #22 on: October 11, 2005, 11:15:38 PM »
Quote
Originally posted by Crumpp
It looks like a typical WWII wingmounted rack.  Absolutely nothing special.

Reminds me of larger version of the ETC 50 rack.

Crumpp



I didn't say it was anything special, Crumpp.  I just said it was smaller and less draggy than the MG151 gondola.  It is.  Krusty seemed to think the opposite was true.


I'm not sure if it is any larger than the ETC 50.  Could the ETC 50 carry a 1,000 lbs bomb?



LRRP

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Offline Crumpp

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« Reply #23 on: October 11, 2005, 11:18:56 PM »
No,

It was limited to 50Kg bombs.  

All the best,

Crumpp

Offline LRRP22

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« Reply #24 on: October 11, 2005, 11:27:36 PM »
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Originally posted by Crumpp
No,

It was limited to 50Kg bombs.  

All the best,

Crumpp


 

Wow! 3 minutes- that was quick...;)


LRRP

Offline Kurfürst

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« Reply #25 on: October 12, 2005, 07:00:37 AM »
Quote
Originally posted by LRRP22
Have you ever actually looked at a P-51's wing racks?  





Not exactly the draggiest appendage imaginable, is it?







.



You can argue as long as you want, LRRP2. For you, the Mustang is always better, in everything. You always argue about that.

Now the facts are, regardless of how you debate them or what picture you post, is that the documented speed loss noted for the Bf 109 gunpods is 5 mph at SL, for the Mustang wing racks it`s 8mph. Sorry, that's what the docs say, it was not me or other who made it up, so try to live with it.

If we consider the loss of speed with other bombracks, ie. the (single) ETC 500 is stated to chop off 8 mph at SL on the Bf 109, and the (single) ETC 501 is said to chop off 10 mph of the FW 190 SL speed. In fact when the Russians tested a G-2 with and without gondies, they found the top speed at altitude to be 649 vs 666 kph, ie. 17 kph or 10mph difference.

 Considering the Mustang carried two bombracks under the wings, 8 mph at SL, and 12 mph at altitude or 20 km/h.

And frankly, this is what I'd expcept. Regardless how you boast on how 'ultra clean' it was, there was nothing special about it. It looks like any other bombrack - even the picture you posted shows nicely what makes up for the drag, it's mounted on the middle of the wing, not near the leading edge hence when the airflow hits the rack it will cause more turbulance; the lines are quite abrupt, no smooth transition again - have you ever wondered why aircraft designers are so fond of teardrop etc. shaped surfaces instead of 'box planes'? And look at the bomb shackles, there are 4 of them as I can see, and they are quite big. Drag is not related to area, (ie. the wing size analogy), but the smoothness of transition. Even the IFF aerial was counted with 2mph speed loss as far as I can remember. It isn't about 'looks'.

Point is, the Mustang D's max speed is usually given without bombracks in most sources, ie. 703 kph at altitude, and it wasn't representative of the RL - if in good contition! - aircrafts performance since it almost without an exception it always carried bombracks for DTs on escort missions; in fact the aircraft's top speed was around 670-680 kph with those racks at altitude. It was discussed a while ago, even you agreed with it.
« Last Edit: October 12, 2005, 07:31:21 AM by Kurfürst »
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Offline Kurfürst

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« Reply #26 on: October 12, 2005, 07:03:23 AM »
Quote
Originally posted by LRRP22
Ah, that's probably the reason- 9 kph at 500kph for the 109, while the Mustang's 12 kph loss at SL was measured between 600 (USAAF) and 640 (RAF) kph..


Which 109 would only do 500kph....? Even the 109F was faster than that, Gs usually topped out at 530-580 kph at SL.

Problem is, even late versions of the 109s like the 109K, which could easily do 607 kph, the gondies make only ~10kph difference.
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Offline TimRas

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« Reply #27 on: October 12, 2005, 10:50:37 AM »
In AH, the speed loss due to gondolas is 9-10mph at SL:
109G-6: 329/338 mph
109G-10: 359/369 mph

The wing racks of P-51 are always included, even if DT's or ord is not chosen (368mph)

Offline MiloMorai

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« Reply #28 on: October 12, 2005, 11:16:57 AM »
Quote
Originally posted by Kurfürst
Which 109 would only do 500kph....? Even the 109F was faster than that, Gs usually topped out at 530-580 kph at SL.

Problem is, even late versions of the 109s like the 109K, which could easily do 607 kph, the gondies make only ~10kph difference.


Proof positive of Barbi's lack of reading comprehension.

Barbi he did not say the top speed was 500kph but at 500kph the gondolas caused a loss of speed of 9kph. He then goes on and says the P-51s loss of speed was measured at 600kph(USAAF) and 640kph(RAF). Ie. at a higher speed where the speed loss should be greater. So do you have the P-51 speed loss at 500kph?

Since you mentioned 190s, the ETC503 caused a loss of speed of 18kph(11mph)/SL. The MK103 gondolas caused a speed loss of 27kph(16.8mph)/SL and 35kph(21.7mph) /20kft.

Offline LRRP22

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« Reply #29 on: October 12, 2005, 12:44:48 PM »
Sigh.  I realize that the Mustang was far from "better, in everything", if only you could make the same realization with regards to the 109.  Apparently, you believe the 109 was so good that it was somehow immune to the fact that drag increases to the square of any speed increase.  After all, that's the only thing that could explain no increase in drag penalty at both 500 kph and 600+ kph.

One thing should be fairly obvious- if you removed the MG151 gondolas from a given 109 and, for whatever reason, replaced them with Mustang wing racks- that 109 would be faster.  Likewise, the P-51 would be slower with gondolas than it would be with racks.

As for the 109K "easily" reaching 607 kph, don't you mean it was  estimated to reach 607 kph under ideal conditions, but only at a power setting that was, at best, rare?



Quote
Originally posted by Kurfürst
You can argue as long as you want, LRRP2. For you, the Mustang is always better, in everything. You always argue about that.

Now the facts are, regardless of how you debate them or what picture you post, is that the documented speed loss noted for the Bf 109 gunpods is 5 mph at SL, for the Mustang wing racks it`s 8mph. Sorry, that's what the docs say, it was not me or other who made it up, so try to live with it.

If we consider the loss of speed with other bombracks, ie. the (single) ETC 500 is stated to chop off 8 mph at SL on the Bf 109, and the (single) ETC 501 is said to chop off 10 mph of the FW 190 SL speed. In fact when the Russians tested a G-2 with and without gondies, they found the top speed at altitude to be 649 vs 666 kph, ie. 17 kph or 10mph difference.

 Considering the Mustang carried two bombracks under the wings, 8 mph at SL, and 12 mph at altitude or 20 km/h.

And frankly, this is what I'd expcept. Regardless how you boast on how 'ultra clean' it was, there was nothing special about it. It looks like any other bombrack - even the picture you posted shows nicely what makes up for the drag, it's mounted on the middle of the wing, not near the leading edge hence when the airflow hits the rack it will cause more turbulance; the lines are quite abrupt, no smooth transition again - have you ever wondered why aircraft designers are so fond of teardrop etc. shaped surfaces instead of 'box planes'? And look at the bomb shackles, there are 4 of them as I can see, and they are quite big. Drag is not related to area, (ie. the wing size analogy), but the smoothness of transition. Even the IFF aerial was counted with 2mph speed loss as far as I can remember. It isn't about 'looks'.

Point is, the Mustang D's max speed is usually given without bombracks in most sources, ie. 703 kph at altitude, and it wasn't representative of the RL - if in good contition! - aircrafts performance since it almost without an exception it always carried bombracks for DTs on escort missions; in fact the aircraft's top speed was around 670-680 kph with those racks at altitude. It was discussed a while ago, even you agreed with it.