A2A P51 Mustang AccuSim is out!

[John_Thomas 0]

I really want to like this plane - it has some tremendous modeling in the virtual cockpit, along with advanced animations and external details; truly a wonder. I have reservations about the some aspects of the flight modeling, however. The roll rate seems very slow for a P-51, and I really can't detect that the Accusim P-51 rolls any faster than the Accusim P-40. In real life there should be a very dramatic difference in roll rates between these two aircraft.

 

I'm not sure if this is a limitation of the flawed ground friction physics modeling inherent in FSX itself, but the the way torque is modeled on takeoff seems sloppy to me. This of course is a purely subjective opinion on my part. Nevertheless, the Accusim P-51 seems to intially pull to the right initially as power in applied (this sure doesn't seem correct) before correctly causing a pull to the left as power builds. The tire friction modeling seems not right and it's quite difficult (at least for me) to maintain center-line as power is increased without wobbling from side to side. I don't know how to explain it, but the tires just don't seem to be griping the asphalt with the correct amount of friction. In real life the P-51 is reported to be quite stable on takeoff roll when correct rudder trim is applied. The Accusim P-51 just seems to me to be too unstable in this regard. Again, this observation is purely subjective.

 

The actual Accusim engine physics are a wonder to behold though; really makes one feel like they are flying a living, breathing, oil sucking machine, so to speak. A2A are truly masters at this particular aspect of simulation.

 

The manual has some shortcomings - there are no published takeoff or approach speeds. There is also no explanation of how to manage fuel tank switching other than the advice of using the left tank for takeoff. Perhaps the manual was a little rushed or this is simply an oversight.

 

I'm not trying to bring A2A down in the least, believe me. I own several of their aircraft and each is among my most favorite to fly in FSX because of the precision modeling and attention to the smallest details, most especially the Accusim technology. The Accusim P-51 to me just seems a little rough around the edges here and there at present, but I'm sure A2A will address any issues down the road.

[Nyxx 6,993]

Is this based on your first hand knowledge of the P-51 or is what you "think" it should be like?

 

I have no idea, but since A2A spent so much time with a real P-51 if what your saying is true then I would be very surprised indeed.

 

With out flying the P-51 IRL I personally would place a lot of faith in A2A to get it right just how the P-51is, not what flightsim people might presume it might be like from our arm chairs.

[Ponk 51]

Effectively, all A2A AccuSimmed products are two-tier: You can buy them without the AccuSim add-on, or you can buy them with it. You can add the AccuSim add-on at a later date if you have bought the aircraft without the AccuSim package too, although since they usually throw in a bit of a discount when you buy both the aircraft and the AccuSim add-on for it at the same time, then it makes sense to get it all in one go if that is what you eventually envisage doing.

 

All of this is basically a legacy of the Wings Of Power AccuSim B-17's development. The A2A B-17G was originally made without the concept of AccuSim being around, then A2A came up with the AccuSim concept and made it available for the B-17, so the process is now typical for A2A creations, in that most A2A aeroplanes will be available in two flavours, with, or without Accusim. Actually, most of them are great even without it, but they really go to another level when AccuSim is added, with much more realistic engine operation, and more sophisticated wear and tear and maintenance simulation taking place.

 

So it all boils down to whether having to work the engines properly and worry about such things as overboosting, fouling the plugs, over-revving, overheating, cooling shock damage on descents, heavy landings and all that kind of thing is something which appeals to you. If it does, then AccuSim will float your boat, since all the things you do have lasting consequences, i.e. if you over-rev the thing on take off and blow a couple of piston rings, dropping the compression a bit, then your aircraft will smoke a bit as it burns oil seeping past the piston rings and lose some power too, and the next time you fire it up for a flight in FSX, it will still be doing that unless you take it into the virtual maintenance hangar and fix it up. On the other hand, if you just want to fly the thing around without worrying about all that stuff, then you can still happily enjoy the A2A P-51 without all that persistent wear and tear and damage modeling and for a bit less money.

 

Since aircraft such as the P-51 are hugely expensive to run in real life, AccuSim gives you an insight into why that is so. For example, unlike your car, where you might use the same spark plugs for literally years, a Rolls Royce or Packard Merlin engine when run at high power is likely to require a change of spark plugs after about twelve hours of operation if it is to keep on putting out full power. And this is just one set of relatively inexpensive components on a P-51 Mustang, so you can see why it is now almost exclusively a rich person's toy in real life, although having the AccuSim add-on for any A2A aeroplane will give you an interesting taste of what that means when it comes to keeping one of those old warbirds going.

 

Al

 

Thanks for taking time to explain it so clearly, really helps now!

 

Cheers

 

Iain

[Nyxx 6,993]

It might have been idea to have done

@Chock

"Thanks for taking time to explain it so clearly, really helps now!

 

Cheers

 

Iain "

 

Saving a great big wall of repeat text.

[Ponk 51]

Good idea :)

[John_Thomas 0]

Is this based on your first hand knowledge of the P-51 or is what you "think" it should be like?

 

I have no idea, but since A2A spent so much time with a real P-51 if what your saying is true then I would be very surprised indeed.

 

With out flying the P-51 IRL I personally would place a lot of faith in A2A to get it right just how the P-51is, not what flightsim people might presume it might be like from our arm chairs.

 

Well, hopefully you noticed I said earlier, "this is my subjective opinion". :) Nope, I sure haven't ever flown a real P-51, but by doing side by side comparisons I'm seeing practically the same roll rate between the Accusim P-51 and the Accusim P-40. If you happen to own both aircraft, I invite you to test them yourself and compare.

 

The P-51 was legendary for it's unmatched roll rate. The P-40, I think most people were surprised it could even fly inverted. :)

[tf51d 284]

Well, hopefully you noticed I said earlier, "this is my subjective opinion". :) Nope, I sure haven't ever flown a real P-51, but by doing side by side comparisons I'm seeing practically the same roll rate between the Accusim P-51 and the Accusim P-40. If you happen to own both aircraft, I invite you to test them yourself and compare.

 

The P-51 was legendary for it's unmatched roll rate. The P-40, I think most people were surprised it could even fly inverted. :)

 

Well I have, and I can tell you this model is very close to the way it actually is, closer than any other FS model, including the original A2A Mustang.. I took it through it's paces last night, through the maneuvers I flew through, and it seems to fly just right. Remember a lot in a 51 depends on it's configuration. Normally you would want to make sure your center fuel tank is low to perform aerobatic maneuvers. This is why on long missions they would drain the center tank then the external tanks, so by the time they reached the point they were likely to meet the enemy, they would be properly configured to combat the enemy. Here's the video's of my flight, that you can compare

 

[CoolP 283]

On the video. Lucky you, Tom. Must have been a great experience.

I had to laugh on the comment for part3.

[Scott - A2A 164]

I really can't detect that the Accusim P-51 rolls any faster than the Accusim P-40. In real life there should be a very dramatic difference in roll rates between these two aircraft...

 

The P-51 was legendary for it's unmatched roll rate. The P-40, I think most people were surprised it could even fly inverted. :)

 

John, you may be mixing up the P-40 with another aircraft. The P-40 is well known for having an excellent roll rate. Here is a chart that compares some well known wwii aircraft:

 

Scott.

[Scott - A2A 164]

John,

 

I want to amend my post as just did a roll-rate test in our P-40, and I can see that we should have more of a drop off of effectiveness at very high speeds. We have another test by the RAF on the P-40B which also bears this out. We'll make sure this change makes it into the next core update for the P-40.

 

However, you are probably victim to many WWII era aircraft being simulated with over-blown roll rates. Except for a few, as you can see in the chart, these aircraft do not roll like jets. They are slow rollers, but as you can see, the P-40 was quite maneuverable. I think this is just another reason why many take issue with claims that the P-40 was outdated at the start of the war. Clearly, the P-40 was a lethal opponent to the Zero.

 

Scott.

[ESzczesniak 128]

In real life the P-51 is reported to be quite stable on takeoff roll when correct rudder trim is applied.

 

This is not an accurate statement. The P-51D with the torque coming form the engine is...well, a Mustang. The rudder trim gets you in the ball park, but is by no means a complete solution. Careful rudder control is required throughout the roll, particularly during application of power and tail lift off.

 

I will have to find the reference again, but because of the tough torque effects the Army Air Corps actually started endorsing takeoffs with 46 inches of manifold pressure rather than 61 inches when allowed by field length. This was to lessen the torque effects and in particular help during transition training.

 

During tail lift off, the required rudder inputs are well known to vary and require careful balance and quick responses to whatever the tail seems to be wanting to do. Once the tail transitions and is up with the aircraft standing on the two mains, the required rudder input is much closer to the trimmed 6 degrees right. You can see this "dancing" on the rudder very clearly in many you tube videos of the Mustang takeoffs. A good pilot will keep the airplane straight, but rudder is often dancing all over to keep it straight.

 

The DCS P-51D beta was recently released. It has a very similar feel on takeoff roll and got very similar criticisms from jet jockeys who were used to shoving the throttles forward and going straight down the runway (they're previous release was an A-10C). This was discussed at length on their forums as I'm sure it will be here. Simply, this is just not how a high performance prop such as the Mustang behaves.

[tf51d 284]

I will have to find the reference again, but because of the tough torque effects the Army Air Corps actually started endorsing takeoffs with 46 inches of manifold pressure rather than 61 inches when allowed by field length. This was to lessen the torque effects and in particular help during transition training.

 

If you watched the second video of my flight, you'd see takeoff roll had a graduated level of power thoughout, 40inches, 46, then 55. Even then rudder had to be used. This was the one phase of flight that the Pilot (Lee Lauderback) took complete control, because of the Torque effect. After that I had the controls until landing, Once on the ground Lee took back the controls to handle the rudder for the rollout.

[ESzczesniak 128]

If you watched the second video of my flight, you'd see takeoff roll had a graduated level of power thoughout, 40inches, 46, then 55. Even then rudder had to be used. This was the one phase of flight that the Pilot (Lee Lauderback) took complete control, because of the Torque effect. After that I had the controls until landing, Once on the ground Lee took back the controls to handle the rudder for the rollout.

 

I apologize if I wasn't clear. I was not arguing that the rudder would not need to be used with lower manifold pressures. Just that it was a somewhat less aggressive rudder input that seems a bit easier to manage.

[audiohavoc 24]

It is absolutely amazing. Love the metal cooling sound when you shut down the engine. This thing is a masterpiece.

[Guest Mik75]

I couldn't hold back buying it! As an owner of all A2A products for FSX, I thought I could wait a little longer to have some money to spend on other add ons (of newer real world counterparts) being released in the near future. But one can only love the stuff they do at A2A. And they get better with every release. Great product and a must have for sure!