OT Max airspeed of combat aircraft with ordinance vs clean

[strykerpsg]

Gents,

I am trying to convince some self imposed aviation experts about the difference of a manufacturers quoted maximum airspeed is of a clean configuration and wholly different from one with ordinance and fully fueled. For example, his facts on the F-104S are that it's maximum speed should be 1200 knots IAS, not capped at 950 knots when loaded with stores. Is there an article that comes to anyone's mind that might dispel that myth to make clarity more viable in the argument?

I know there's much real world civil and military aviators in this forum that can articulate this much better than I can. My Google/bing search only pulled up manufacturer stats and do no factor in drag of the stores.

Thanks in advance.

[Bjoern]

Whack 'em over the head with a book on the fundamentals of aerodynamics. That should work.

[Dino Cattaneo]

Avialogs has dozens of flight manuals of military aicrafts... they often include the airspeed limitations with different loadouts (actually they always do, unless that information is in a separate document...)...

http://www.avialogs.com/

[Victory103]

You'll be looking for "drag index" charts which will give you various store configs and the expected degraded performance values at a given altitude/speed.

[strykerpsg]

Wow! Thanks guys for the info. I have to admit, the info was a bit overwhelming to dig through initially, but Victory's hint about Drag Index helped dramatically. I have always wanted to own a personal GA bird, but after thumbing through that info, my head hurts..

I'll stick with my virtual flying in FSX and eventually to Prepar3D and reading my much simpler Infantry FM/TC/TMs.

I knew there were more than a few that could be counted on to help me get through that conversation.

[Motormouse]

And,as no doubt Dino will agree, sometimes it's not the drag index of a particular store that is the limiting factor,
it is the nature of the store itself, and its susceptibility to kinetic heating, or whether it creates additional aerodynamic
problems within certain speed ranges.

Ttfn

Pete

[stansdds]

External stores also bring additional g-limitations. This information would be found in the pilot's operating handbook for the aircraft in question.

[strykerpsg]

Thanks team for all the comments and assistance. I paid for a subscription so I could paste some of the scales onto the forum I was defending. In the end, it was to no avail as the 2 I was arguing with could not understand my point I was trying to make to them and instead generated a bigger argument over it all.... so I moved onto another conversation. In the end though, a great website with some great manuals and reference material.

Matt

[Naruto-kun]

Ah well you know what they say....Never argue with an idiot. He will drag you down to his level and then beat you with experience....I don't think there is any honest aviation enthusiast who doesn't realise that no aircraft can reach such speeds with all that drag.

[srgalahad]

If you really want a headache, try to explain the difference between-
Max speed quoted by the manufacturer/operator (for PR purposes) vs max flight test speed vs max operating speed (limits) vs 'don't look now but you are coming apart'.

Then, when the answer comes back as " it says: 1200" see if they know if that's IAS or TAS and Knots or MPH (or even KmpH) and if an altitude(s) is listed for the figure. If they are reading the 'popular press' it's often the case that there is no value for any of the above and even if one is listed then comparisons have to be in the same unit to be valid.

The average 'expert' just wants to be associated with the 'best' so it's like guys comparing the horsepower of their Chevy Cruze in the drive-in parking lot -lots of numbers, no real data, and likely not a lot of understanding of things technical. Of course load-out has an effect; so does even a slight difference in other drag items, and even the particular production version of installed engine (and prop, for those so-equipped), and then there's weight as tested.

Don't even get me started on range vs speed debates...

[fliger747]

For WWII aircraft it can be interesting to obtain and filter through the various factory and military figures for HP, speed etc. It is worth noting that max speed is quoted often at a time limited War Emergency power value at most optimum altitude. Somewhat misleading at best and often the weight at which the test was made unavailable. There are good reasons why the P51-H, as great a performer as it was, never was considered competition for the jets. Turbine engines are capable of running at high outputs for long periods of time whereas piston engines are not.

Max speed, range and payload are three separated corners of a triangle. To optimize, choose one...

[Pluto12]

Hi,
I am agree with Srgalhad,
as we developed the F104S for FSX/P3D, and with many F104 Pilot as friends, and one pilot in my family, I can say for sure that the maximum speed is 750Knots IAS at all altitude. Over the 750Knots the structure will damage and overheating. Even in clean configuration, at sea level, the F104 could reach Mach1,2 (in a lucky day) and it about 750Knots. It has a lot of "excess power" and it could get, probably, more than 750 Knots at sea level.
It is different if we speak about GS, at FL450 Mach2.2 the GS is more or less 1200Knots, so those datas make sense, but the IAS is always under 750Knots. All these datas are readable in the Dash-One or Flight Manual, and there are also the limitation with external store.
Just for example, an F104G with standard configuration with no missiles or bombs, but with WingTips (fuel tanks) and the 2 racks (BL75) under the wing, could reach Mach 1/Mach 1.05 at sea level but with a long time of acceleration. With missiles or bomb under the wings it was impossible, too much drag (at sea level..at high altitude was possible)
Regards
Emanuele

[strykerpsg]

Hi,
I am agree with Srgalhad,
as we developed the F104S for FSX/P3D, and with many F104 Pilot as friends, and one pilot in my family, I can say for sure that the maximum speed is 750Knots IAS at all altitude. Over the 750Knots the structure will damage and overheating. Even in clean configuration, at sea level, the F104 could reach Mach1,2 (in a lucky day) and it about 750Knots. It has a lot of "excess power" and it could get, probably, more than 750 Knots at sea level.
It is different if we speak about GS, at FL450 Mach2.2 the GS is more or less 1200Knots, so those datas make sense, but the IAS is always under 750Knots. All these datas are readable in the Dash-One or Flight Manual, and there are also the limitation with external store.
Just for example, an F104G with standard configuration with no missiles or bombs, but with WingTips (fuel tanks) and the 2 racks (BL75) under the wing, could reach Mach 1/Mach 1.05 at sea level but with a long time of acceleration. With missiles or bomb under the wings it was impossible, too much drag (at sea level..at high altitude was possible)
Regards
Emanuele

Emmanuele,

I fully agree with what you stated as I too referenced the Dash One for the F-104S and it stated exactly what you said. The problem was this dynamic duo was trying to beat up the developers of a naval strategy sim called Command Modern Naval Operations or CMANO, by Slitherine/Matrix. The development team made a choice to limit the maximum speeds of a majority of their Mach 2 capable aircraft to 950 knots, it's not the maximum for many of the aircraft in real life, but a very close approximation to what one would see if the same aircraft were equipped with combat external stores, or even fuel tanks, versus a fully stripped aircraft that's achieving it's maximum speeds and height to climb data. Anyway, the dynamic duo insists that because the developer made this decision, the game is not a true to life simulation and therefore garbage because the F-104S is capable of Mach 2.2.

Even I as a infantryman, know the more kit I put on, the slower I too will go, as would a fully equipped aircraft not have it's maximum airspeed available when carrying full fuel, weapons and external tanks. They are truly jilted because this newer simulation is replacing Harpoon 2/3, for which the dynamic duo has made their own database and this replacement title is making Harpoon's continued Gameplay limited at best.

Anyway, I truly appreciate the great replies and knew I wasn't wrong and as Naruto said, "Never argue with an idiot. He will drag you down to his level and then beat you with experience...." Those two indeed are truly trying to derail and suck the lifeblood out of the development team and have been banned most everywhere except for posting in the Steam review threads. There they do indeed troll, looking to convince anyone willing to listen.