How to dive tactically? (when under attack)

[Istari6]

I've been spending the last month learning the DCS P-47.  In reading about the Thunderbolt, a common theme is the incredible diving capability, a capability that could be used to get away when in trouble.  I've read how Hub Zemke trained the 56th Fighter Group to focus on boom-and-zoom, or do a diving attack through a Luftwaffe formation and using dive speed to get away safely.

The challenge I'm having is that the DCS P-47D 30/40 doesn't seem to behave the way I've been reading about from historical accounts.  Diving seems very challenging in this aircraft, more so than any other DCS warbird I've flown (P-51D, Bf 109 K-4, Fw 190 D-9, Spitfire Mk IX).  

I'm well aware of managing the MP so I don't overboost the engine while diving into thicker air.  The problem seems to be the RPM.  The Double Wasp consistently breaks if it exceeds 2800 RPM for any length of time.   Yet I'm struggling with keeping RPM below 2800 in a tactical situation diving away.  If I have lots of time, I can throttle back first to 30", drop RPM to 2300, then dive at a moderate angle and keep RPM under control.  

But in any tactical situation where I need to dive NOW (or in the next 5-10 seconds to get away), I can't seem to find a combination that will keep my engine alive.  If I start the dive at max combat power (e.g. I'm in a turning fight with a 109 and I'm starting to lose so want to disengage), the RPM seems to stay high even if I try to decrease RPM or throttle moderately once the dive has begun.  If I chop RPM dramatically, then the entire engine stutters and chugs, causing a loss of power just when I'm trying to get away.

How do you all dive the Thunderbolt quickly in tactical situations?  I'm just surprised at how hard it is in DCS to use what was supposed to be the "trump card" of the Thunderbolt design.

 

[kablamoman]

I think this has been reported before, and there is some question as to whether or not the damaging behavior of the slight overspeed is accurate.

I think you can actually achieve a wider range of prop pitch control if you switch to manual mode and coarsen the pitch, which doesn't make much sense to me (you'd think the high-pitch stops would be the high-pitch stops). You could try that as a workaround

Ultimately, I think there is plenty of room for improvement with the prop modeling in a dive (not to mention diving from high altitudes doesn't really seem to generate the kind of behavior it's supposed to in terms of compressibility). Been a while since I messed with the module due to other issues (the fragile engine bearing), so my input may be well out of date.

Edited June 12, 2023 by kablamoman

[grafspee]

According to manual you can overspeed engine to 3050rpm for brief time, looks like devs missed that part when modeling engine.

[Istari6]

Thanks for the responses.  I wonder how this was missed, given how critical the dive is to the Thunderbolt's historical reputation.  The current time you can run to 3050 rpm is probably measured in seconds.  

I don't recall seeing any mention of P-47 changes in recent OB releases.  So I'm assuming this module is currently on the "backburner" and won't see adjustments any time soon.  How do you deal with the current modeling of the P-47 in DCS?  Any tips or tricks on how to leverage the diving capability that exists?  

(Don't get me wrong, I really appreciate the DCS Thunderbolt.  Beautiful modeling, detailed systems, feels "great" - distinct from the other warbirds.  It's just this area of the flight/engine modeling which is taking away one of the P-47s greatest strengths)

Edited June 12, 2023 by Istari6

[The_Tau]

Right now with current modeling when I am going to dive I use Manual prop pitch and decrease RPM to 2500 and RPM tends to stay there throughout the dive. When I start "Zooming" I put prop back to auto and Bob's your uncle.

Edited June 13, 2023 by The_Tau

[Istari6]

Interesting.  Can you pull RPM back to 2500 with the Prop lever on the throttle quadrant, then flip to manual to keep it there?  I'm trying to figure out what I can do quickly under pressure, as a tactical dive (to get away from a bogey on my six or where I'm losing a turn fight).

[Art-J]

I think Tau made a bit of a mental shortcut. Just switching to manual won't help in itself, 'cause the prop becomes a fixed pitch one and thus it's going to windmill and overspeed as well if not adjusted accordingly.

By the way, in auto mode we can't even get to 3000. In a steep dive the engine will rev up to about 2900-2950 in twelve'ish seconds and die.

I suppose the only reasonable solutions available for now are:

a) bind manual pitch to some easily reachable two-way switch on your HOTAS or;

b) perform dives shallow enough NOT to get above current redline of 2750 or;

c) just try not getting in a situation when you need to perform a dive to the deck at all. 

Moreover, since compressibility lock of elevator doesn't seem to be simulated anyway, why not trying to pull up near the redline? Won't help against 190s, but at least the 109 will more likely struggle to follow.

[The_Tau]

Its just when engine overspeeds and goes dangerously close to 3000 RPM then Prop lever becomes unresponsive even when fully back, but manual RPM still works and you can still decrease RPM below critical level. Maybe its DCSism.

And yes, i did map manual pitch to my HOTAS. 

You can dogfight with 190s but not really with 109s and diving is really only thing you can do to survive, when jumped. 

[grafspee]

@The_Tau Automatic rpm control has limited pitch range. Higher pitch only available in manual mode. If you set 2500rpm and in dive you notice that rpm is rising that mean that max pitch was achieved, and moving rpm lever back do nothing.

This is how this works in DCS, does it accurate is another topic.

Edited June 14, 2023 by grafspee

[Fortinero]

You actually can avoid breaking the engine (in DCS, not in real life), like people said, using the manual pitch, real problem is, not only devs missing the fact of the 3050 RPM overspeed limit is not so short, but also how the Jug behavs in the dive and how compresibility is NOT modeled, so fighters like the 109 in DCS will not suffer his effects and will keep with you.

Edited June 19, 2023 by Fortinero

[Istari6]

Yes it's strange that compressibility isn't modeled.  There seems no reason to use the dive flaps in the DCS Thunderbolt.  As for a 109 being able to follow, I wonder if the reduced elevator authority is modeled at high speeds for AI.  Flying the 109 K-4 as a human player, you have to be quite careful in a high speed dive, since the ability to pull out is limited.  That's not compressibility per se, but a function of an airframe being powered to speeds well beyond what it was originally designed for.  I wonder if AI 109s can be led into maneuver kills by trying to follow a fast P-47 dive to low altitudes?