Douglas A-26 Invader: Rate of Turn (This is Fascinating)

[KJ_Lesnick]

I was watching a documentary on the A-26 which included USAF F-22 instructor pilot LTC "Max" Moga in it: It actually stated that the A-26 could (at least under some altitudes) could turn inside an Me-109. 

I don't know if this is weight specific, but I assume the Me-109 could pull around 8-10 g right?

[sandiego89]

Well there are a variety of factors affecting turn rate: wing loading, power, altitude, wing design/camber. etc.  Also there is instantaneous turn and sustained turn rates.  Looks as though you are referring to sustained rate here. 

You can find circumstances where a seemingly less nimble "bomber" can out turn a "fighter".  Most likely place is at high altitude where a bigger wing can make the most difference.  A plane like the A-26 has a good sized wing for its size, good power and at lower weights at altutude I would not find it that surprising that it could get inside some fighters. 

Perhaps the best examples of this are the B-36 and Vulcan, which did quite well up high.  Both had large wings/low wing loading and plenty of power.  They could still manuever up high when fighters trying to manuever with them might fall out of the sky. 

The 109 was not the best puller, some stories of structural failure of pulling too tight, and pilots treating it respecfully so.

Unsure what the G-load rating on a 109 is- but surely the pilot could not stand 8-10g in a sustained turn.  Pilot limited (as were most designs of the era)     

[Captain Canada]

The CWHM used to house one done up in markings from French Indo-china, and that thing could turn ! Think of how many years they were used as water bombers too....

[Mossie]

I found out recently that PB4Y-2 Privateers would dogfight Japanese aircraft and that several crews were given ace status.

[PR19_Kit]

The idea of a long winged Privateer dogfighting anything just boggles the mind! 

They did have lots of guns though so maybe they could do it just by flying straight and level?

[Logan Hartke]

VPB-117 flying PB4Ys got 58 kills in WWII and had five "ace" crews.

http://www.history.navy.mil/avh-vol2/Appen4.pdf

The maneuverability of the PB4Y-1/B-24 has often been maligned by pilots of a sister service – it has been said that the plane was "clumsy and very tricky to fly." Sutton's action, and many other Navy pilots; actions, have demonstrated that the plane can be flown "like a fighter," at least at low altitudes. Most of the Navy plane commanders, however, had the advantage of experience before becoming patrol plane commanders (PPC). The PPC's normally had well over 1,000 hours of flight time and a combat tour as a copilot, before flying as the plane commander.

http://vpb-117blueraiders.com/Squadron_History.html

Cheers,

Logan

[perttime]

Most of the Navy plane commanders, however, had the advantage of experience before becoming patrol plane commanders (PPC). The PPC's normally had well over 1,000 hours of flight time and a combat tour as a copilot, before flying as the plane commander.

It must be an advantage to have some experience. Even better if you know what your aircraft and crew can do - and not do - AND what your opponents can and cannot do.

From reading just some fighter ace accounts, they didn't often win because they were much faster or turned harder. They won because they had situational awareness and could play the situations to their advantage. Know where everybody is and what they are capable of doing from that position. Know who is a threat now, or could be a threat in 2 seconds time. Trick your opponent into doing something that gives you an advantage. Don't make mistakes that give your opponent an advantage.

[rickshaw]

The P-61 was often credited, despite it's not inconsiderable size with the maneuverability of a much smaller fighter at altitude.  Northrop achieved that with both a long wing loading and various aerodynamic "tricks" such as using spoilers, rather than ailerons and combat flaps.  Supposedly it was able to out turn a Mosquito.   The key though, was "at altitude" where big wings help, whereas most fighters have small wings.   B-47s often outmaneuvered MiG-15/17/19s at 50k feet when penetrating Soviet airspace in the 1950s.  They were faster and flew higher than the MiGs could reliably achieve.   Canberras did similar, particularly the PR.7s and PR.9s which regularly intruded into Soviet airspace.

[Logan Hartke]

I also know that certain pilots took advantage of the the structural strength of US aircraft and would pull tighter sustained turns than their opponents in many cases because they knew their aircraft could take it. The Australian pilot, Nicky Barr for example, had this to say about the P-40 Kittyhawk.

I would evade being shot at accurately by pulling so much g-force ... that you could feel the blood leaving the head and coming down over your eyes... And you would fly like that for as long as you could, knowing that if anyone was trying to get on your tail they were going through the same bleary vision that you had and you might get away. I had deliberately decided that any deficiency the Kittyhawk had was offset by aggression. And I'd done a little bit of boxing – I beat much better opponents simply by going for [them]. And I decided to use that in the air. And it paid off.

Cheers,

Logan

[KJ_Lesnick]

sandiego89

Considering LTC Moga said it could "turn inside a Me-109" and seemed stunned by this revelation, it would appear he was talking about turning arcs.  Turning arcs when combined with speed become g-loads (a=v^2/r) and considering the A-26 only had a single-stage blower and a service ceiling of 22,000 feet or so, this would appear to be something that would take place at altitudes of around 10,000 to 15,000 feet.


Captain Canada

When they were turning, what bank angles were they using?  You can infer g-load from that...


rickshaw

1. The P-61's maneuverability wasn't just surprising (to me) because of it's size, but because it looked like such a clunky beast!  It didn't really have a light wing-loading, it's aspect ratio was slightly high, but it's flaps being nearly full-span would have a substantial effect on lift when deflected (something made possible by the zap flaps).  I remember hearing statements that did say the following

• The P-61 could out-turn DH.98, though it had an inferior rate of roll
• The P-61 could out-roll the DH.98, though it could not turn as fast

The first was more common: I'm not sure truthfully how many g's the P-61 could pull, but at least some DH.98 variants could pull 8g.

2. I didn't know the B-47 could out-turn MiG-15/17/19 at 50,000 feet: I remember hearing they were riding the coffin corner under those conditions so that's a surprise.


Logan Hartke

The P-40 was one tough beast of an aircraft: Hehe, they survived rammings against other aircraft (some intentional which were counted as kills)

[Logan Hartke]

I think even more impressive than outmaneuvering Mosquitos was the P-61 outmaneuvering P-38s. I read that the main company test pilots for Northrop and Lockheed were good friends and had a mock dogfight between the P-38 and P-61 over L.A. with the Black Widow trouncing the Lightning. Not bad for a fighter the size of a B-25.

Cheers,

Logan

[KJ_Lesnick]

Everybody

Does anybody know what the Me-109's maximum g-load from 5,000 to 15,000 feet is?  I'm searching the web and I can find all sorts of amazing stuff on the plane but not the g-load!


Logan Hartke

They were able to out-turn the P-38?

[perttime]

Didn't find G loads... but it seems that high G was feasible for very brief moments only, or pulling out of a dive, anyway. You couldn't maintain much speed and energy with the period power plants, if you kept pulling a lot of G in level flight.
How hard you could turn without stalling or slowing down too much seems to have been more of a limiting factor.

This might give some insight into that:
http://www.combatsim.com/htm/nov98/energy-man2.htm

[KJ_Lesnick]

perttime,

Didn't find G loads...

I know!  It's like you can find almost everything except that one figure.

As I but it seems that high G was feasible for very brief moments only, or pulling out of a dive, anyway.

True but that will give you a turning arc figure

As for your link, maybe it's right maybe it's wrong but I had almost sworn I read something which listed the mustang as able to do +/- 10g

[perttime]

As for your link, maybe it's right maybe it's wrong but I had almost sworn I read something which listed the mustang as able to do +/- 10g

For Mustang, I found this:

P38 and P-51 were designed to 8g limit and 12g ultimate but in each case that was linked to a specific gross weight. For the Mustang, limit load of 8G applied to 8,000 pound gross weight which was middle range for an XP-51 and P-51A. By the time the P-51D was operational a limit load for 10,000 pounds Gross weight was 6.4 G

http://www.warbirdinformationexchange.org/phpBB3/viewtopic.php?f=3&t=39803&start=15

I think that means you could safely pull 6.4 G in a 10,000 pound (gross) P-51D, and risked catastrophic failure if you pulled 10 G or more.
Obviously, the weight you are carrying affects the amount of stress you are putting on the airframe.

In some discussions I got the impression that British fighters were built to lower G limits than US designs.

At some point Bf 109 (F model?) were built to lower limits than needed, or with lower quality, and that caused some failures.