Crumpp

I would welcome it too. The original posters assertion is meaningless without more measured data. I think we need to present that measured data, draw a conclusion, and then submit a bug report if necessary before we ask Yo-Yo to drop working on other things we need like maps and more aircraft (like my P-47 :smilewink:). I personally would like to know more details and find the original documentation on the USAAF G-pants.

Shadepiece, Welcome to DCS! I can see your confusion at my reply. To clarify, there should not be a slider that goes between 250 yards and 350 yards but players should have a choice between 250 yards OR 350 yards in the P-47 series. That is what the operating instructions say the bore sight data was available in the standard zero targets. If approved bore sight data is not available, it probably was not available to the armorers to correctly bore sight the weapons. As you can see from reading the FM, it is a complicated issue and the intent it was not to be altered in the field without a specific tasking from higher. It is no different to me than unauthorized engine settings. Did that happen? Yes it did and I am equally positive pilots died as a result. Unfortunately we only hear from the few that got lucky. DCS does not model over boosted because it is an outlier. They understand how airplanes are maintained and correctly model only approved engine ratings. That same level of realism should apply to weapon systems.

You are correct...the details matter. I draw my conclusions after examining the reports. Understand too that onset rate, pilot disposition (relaxed, trained, untrained, etc), and equipment also matter. Most importantly, the mathematical relationship is applicable. The 40% I listed is not an absolute but an illustration of the general mathematical relationship. It is also not threshold but endurance. Two different things but can lead the casual observer to the wrong conclusion. Although both pilots may pass out at a 5.5G threshold at a given onset rate, the fact one can endure it longer won't make much difference to the average player. He will just note that one pilot passed out and the other did not. Onset rate changes everything, the details matter, and seat inclination is important to G-tolerance. That is the generalization the studies show us. It is not as simple as "seat inclination = X number it G increase under all conditions". That is why fighter and aerobatic aircraft designers pay attention to seat angle.

Instability also does not mean maneuverability. That is a common misconception. Modern maneuverability criteria include demonstrating the pilot can perform a turn and hold a precise acceleration. Usually 3-G's IIRC... An unstable aircraft will not maintain a precise acceleration but will fluctuate overshooting and under shooting the targeted G load. The pilot has to constantly control it to maintain load factor.

http://avstop.com/ac/flighttrainghandbook/elevatortrimstall.html The stability curves were measured in clean configuration. Configuration changes can move the Aerodynamic center and change the stability characteristics of the aircraft. CG position changes the stability margin and can also change the stability and control characteristics. The Spitfire for example was statically and dynamically stable at forward of normal CG position all the way to the forward limit. It was only at normal to the aft limit that it exhibited longitudinal instability. In landing configuration many World War II designs exhibited instability.

The pilot has to be there. The first thing I noticed was the standard target shown in the first frame.

The information you post is good information. You are simply passing on what you read. I welcome the discussion. I am simply pointing out the anecdote is not proof and open to interpretation.

NATO round up of High Physiology research: In summary.... 0-15 degrees incline is considered vertical seating with little to no effect. Think about it...nobody sits a 90 degree upright seat even at most dining room sets. :smilewink: 16-30 degrees was found to be a good compromise between G-tolerance effects and degradation of the pilots vision and breathing found at high incline angles. 30(+) resulted in vision scanning impairment and breathing difficulties Only one report found no difference between 13 degrees and 30 degrees. The other reports list noticeable effects due to seat angle and all found a similar mathematical relationship. A function of the vector resolution over the distance from the eyes or brain to the heart. The basic relationship is approximated by the inverse of the cosine of the angle and the G-load. Using the 14 degree and 25 degree found by ARKROYAL measurement of internet drawing, I technique I do not recommend for gathering data... That is proportional to 7% at 1G and 40% at 6G as noted by Burton and Shaffstall. As for leg elevation: The data is divided. Some show a benefit while others do not. http://ftp.rta.nato.int/public//PubFullText/AGARD/AG/AGARD-AG-322///AGARD-AG-322.pdf Dirkan, The results are absolutely believable. The results of a completely upright pilot without an G protection could withstand 15G's without blacking out while a 30 degree incline pilot blacks out at 5 G's is also possible. You are missing the most important factor...ONSET RATE. Without it, the claim: Is totally meaningless. :( Lastly, the G-suit effects are also listed in the report I posted. Early Anti-G protection ran the gamut from meaningless to effective. Finding some good data on the USAAF G-suit protection results vs Onset Rate would be very good.

You most certainly can get some significant G tolerance out of pilot seat position. I would welcome an intelligent mature discussion and thank you for posting. I think it would benefit the community. I think I have this report. You are absolutely right and the data is correct but can you link the entire report so all can examine the details. It can be deceiving without the onset rate and disposition of the test subjects. I have multiple reports on pilot G-resistance so we can "get to the bottom" of this to see why every modern fight designer considers seating position effect on G-tolerance. You will have excuse me though for the next few days. I am at the frontside of a 4-day and will be home from work till the end.

Post the RAF instructions for sighting in aircraft weapons and nobody will have to guess. Until then the only facts regarding service policy are the USAAF instructions and the knowledge obtaining correct ballistic data / aircraft angle of attack / gun site alignment cannot be done by shooting point of aim point of impact on a range. Do you know what I mean by that, statement? You understand the physics and you that you cannot just drag the aircraft out to the range and align the sight with the guns like you do a hunting rifle? I know the weapons on the Spitfire Mk Ix. I will restate my last point. Just because Johnson had a decision to make does mean he "did his own thing". P-47 pilots in the USAAF could make the same decision. They had to make a choice between 250 yards and 350 yards. Look at the data and you will see there are significant differences. You assume that because he had a decision to make he was doing his own thing. He simply could have been choosing between authorized bore sight data for standard patterns. Given the physics involved, that seems likely to me.

Consider: 1. RAF/RCAF is not the USAAF. Different country, different service, different rules. Especially with the early rifle caliber weapons of the RAF fighters, close range spot harmonization was pretty close to ideal! 2. Spot harmonization is exactly what the USAAF warns against, however. As both the TM and FM explain, the site line and AoA data will not be correctly aligned so the airspeed will be unknown and point of aim point of impact zero on the ground will only occur at 0 mph airspeed if the bore sight data is not worked out by the engineers. 3. Just because he had a decision to make does not mean he did his own thing. 4. Johnnie Johnson was a national hero in his own time. Far from the average pilot and the fact he did it does not prove it was available to everyone else.

Not that I am aware of.... A stable airplane does not necesarily mean a hands off airplane. It means it will seek the speed for which it is trimmed. In RL, it is natural and intuitive to most pilots to feel the trim but can be difficult on a computer due to lack of feel. Just as in RL...fixed trim tabs are a non-issue but on a computer require constant attention. In RL....you simply hold a small of control input. It has never been excessive or even noticable. It is just natural. If you have "trim on a slider" you can simulate this by simply triming the axis to hold the control input. My feet are not lazy RL because with the exception of the transport category aircraft I fly at work, my piloting has been mostly in high performance taildraggers. My brain and feet are attuned to keeping the ball centered and wngs level.

Maybe you missed what I wrote or it did not sink in on your P-51 comparison?

Exactly. There is no where in any of the instructions that say adjust to the whims of an individual. The stipulations are being "tasked from higher", in other-words, Aberdeen, the manufacturer, or the service could delegate a harmonization mission. In FM 200-1 Introduction, we see Aberdeen's instructions to use M2 Ball ballistic data for M8 API ammunition because they felt it was close enough as they had not done a specific bore sight chart for it. The instructions allow them to task one of the 8th USAAF Quartermaster stations to derive the data and produce a bore sight chart if they so choose. The local "tactical situation" is not referencing a single airplane. It simply leaves it open for operational flexibility at the organizational level. For example, the 75mm gun data provided in FM 200-1 without a doubt is the result of Pappy Gun's ideas for the B-25's in the Pacific. Operational Flexibility allowed the 7th USAAF to produce bore sight and ballistic data for that weapon installation as a result of the local tactical situation.

The Luftwaffe measured stability curves for the Bf109G series show a strong static and dynamic longitudial stability.

Which is an excellent reason why they did not allow individual harmonization patterns. :thumbup: With standard data, only the gun that is being changed would have to be aligned with the 1000inch boresight target. It could be done in the hanger and would take a lot less time. The aircraft has to be jacked, placed on stands, plumbed and leveled each time you boresight. Ideally, you would confirm it by shooting the guns on a zero range. That means taking the aircraft out to the range, jacking it back up, implacing the stands, plumbing and leveling again. You also have to sight the gun camera system in as well. It is not a quick process.

http://www.differencebetween.com/difference-between-static-stability-and-vs-dynamic-stability/

Actually, there are quite a few aircraft that are not stable. They require double control inputs and can be tiring to fly. Static stability is the initial tendency of an airplane. A statically stable aircraft will move toward trim speed after an impulse the moment the stick is released. A statically unstable aircraft will move away from trim speed initially. Statically neutral aircraft will stay at whatever speed the stick was released at after the impulse. Dynamic stability refers to stability over time. The more dynamically stable, the fewer oscillation periods and faster the impulse is dampened and the aircraft returns to trim speed.

You proved it!! :thumbup: Seriously, not even going to explain how silly this is becoming. You drew your line on the side of the seat...not the back. Just look at the axis from the heart to the brain.... Just go sit in an FW-190 cockpit and then a P-51. You will notice a big difference.

The manuals are posted. It is an involved process. Probably at least 7-8 hours to boresight and zero.

Cause it does not make any difference Grapejam? You can take it personally and hate me but it is just a fact the pilot seating is more advantageous for G-tolerance in the FW-190 series than the P-51. :smilewink:

There is not a complete lack of options in the game: You can do it right now on your server. Come up with all the harmonization patterns your heart desires!! I am all for it. Let's not waste limited development time on such a gamey addition as a slider. Save that stuff for the warthunder crowd.

Which the math is NOT INTENDED FOR USE IN THE FIELD....... In otherwords, it is not intended for each pilot to have his own harmonization pattern on a whim. Negative Ghost-rider.... Military jargon is specific. Station refers to an installation. In this case, Armorer is an Ordinance Corp function which falls under Logistics and there were two Quartermaster stations in England for the 8th USAAF: http://www.gitrace.org/stationnumbers.html

And they were not stupid enough to let such an important task get botched thru well meaning ignorance either. Each individual station does not mean each pilot or even each squadron. It means it is an organizational level task. In otherwords, it is not the gamey slider you are asking for! :thumbup:

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