Absolute or Service Ceilings?

[Buzpilot]

From Wiki;

Service ceiling

The service ceiling attempts to capture the maximum usable altitude of an aircraft. Specifically, it is the density altitude at which flying in a clean configuration, at the best rate of climb airspeed for that altitude and with all engines operating and producing maximum continuous power, will produce a given rate of climb (usually 100 feet per minute climb or 30 meters per minute, and 500 feet per minute climb for jet airplanes). Margin to stall at service ceiling is 1.5g.

The one engine inoperative (OEI) service ceiling of a twin-engine, fixed-wing aircraft is the density altitude at which flying in a clean configuration, at the best rate of climb airspeed for that altitude with one engine producing maximum continuous power and the other engine shut down and feathered, will produce a given rate of climb (usually 50 feet per minute).

However some performance charts will define the service ceiling as the pressure altitude at which the aircraft will have the capability of climbing at 50 ft/min with one propeller feathered.

 

From this reading, and with the new planes from different 3'rd part developers, where some of the planes are capable of more than double the altitude of Service ceiling, something need to get cleared out.

One example. The A-10C has a celing at a clean configuration for 45,000 feet, this means it still would be able to climb at about 500 feet pr minute at that altitude.

Currently the DCS A-10C have a Absolute Ceiling at about 36,000 feet and a DCS official service ceiling at 33,000 feet, 10,000m.

Different sources all say 13,700, or 45,000 feet (one claimed 45,000 13636m)

 

And also for Jets the maximum continous power is without afterburners, so there's probably a lot for ED to do here, or will the 3'rd party Developers planes get nerfed down to ED's current standard?

[EtherealN]

See below:

 

 

Be careful with Wikipedia. ;)

 

And also for Jets the maximum continous power is without afterburners, so there's probably a lot for ED to do here, or will the 3'rd party Developers planes get nerfed down to ED's current standard?

 

Explain?

Edited September 21, 2012 by EtherealN

[Yskonyn]

Just because something doesn't fit into the realm of Wikipedia, it means it is nerfed?

 

You might want to word your post a bit differently. People might get pissed off and consider this bait when you come in with a streched leg like this.

 

Be careful, young padawan!

Do not meddle in things you have no proper knowledge of! ;)

 

(Or some other Jedi-ish action line)

Edited September 21, 2012 by Yskonyn

[Buzpilot]

See below:

 

 

Be careful with Wikipedia. ;)

 

 

 

Explain?

 

I'm no expert, for all I know the wiki part are written for civilian planes.

From the data sheets, it looks like 500fpm is Combat ceiling, and 300fpm are Cruise Ceiling, and with afterburner it looks like the F-16CJ (F-100 engine) is capable of about 15,000 extra feet, and still able to climb 500fpm.

And it looks like service ceiling has 100fpm.

But, there are a number of older fighterjets that can reach far above it's service ceiling.

 

Altitude records;

F-4 Phantom II, December 6,1959 98,557 ft

F-4E Phantom II,Service ceiling 60,000 feet

 

F-104C December 1959 103,389 ft in 15 min 4.92 seconds.

Service ceiling 50,000 feet (probably because of the small wings)

 

In 1984, during a major NATO exercise, Flt Lt Mike Hale intercepted a U-2 at a height which they had previously considered safe from interception. Records show that Hale climbed to 88,000 ft (26,800 m) in his Lightning F.3 (From wiki too)

Lightning F-3 Service ceiling 54,000 feet.

 

I'm not claiming that theese planes can stay at those altitudes, it's more like trading speed for altitude, but the planes in DCS seems underpowered.

 

The A-10C ingame has a service ceiling 10,000m, or 33,000 feet, but I only find 45,000 feet anywhere else.

 

http://www.af.mil/information/factsheets/factsheet.asp?id=70

Edited September 21, 2012 by Buzpilot

[Buzpilot]

Just because something doesn't fit into the realm of Wikipedia, it means it is nerfed?

 

You might want to word your post a bit differently. People might get pissed off and consider this bait when you come in with a streched leg like this.

 

Be careful, young padawan!

Do not meddle in things you have no proper knowledge of! ;)

 

(Or some other Jedi-ish action line)

 

I'm not trying to put out a leg or anything, it's just that this seem to be too stange to be true, compared to everything else i read.

You never tried to reach service ceiling in FC1.12 with the F-15, or you would understand why I'm worried.

And no, I'm not a 'young' padawan, so shut your little mouth!

[Yo-Yo]

As one can see in this charts the ceiling very much depends on the GW and DI has less effect on it.

Talking about it the sources like wiki always forget to mention what GW is for the ceiling they quated. So this kind of info is almost useless and can confuse.

 

THe same situation is for climb rate. It has sense only if the climb rate is specified as

XXX fpm @ XXXXX lb @ MIL/WEP/MAX, etc power

 

 

 

THe second cause for misunderstanding is the fact that often the service ceiling is limited for non-physical reasons/ For example Su-25 can fly up to 14000 m, but the service ceiling is limited at 7000 due to cockpit pressurisation and pilot health reasons.

Edited September 21, 2012 by Yo-Yo

[Tango]

A civilian aircraft has reached its operational ceiling when:

 

* It is at minimum reserve fuel, and;

* It can't sustain a climb rate of greater than 100 ft, or;

* It has reached the maximum operational altitude for pressurization/oxygen systems.

 

It's service ceiling is often much lower, as the result of payload, fuel weight, and atmospheric conditions.

 

I heard, but have no documentation to support this, that a combat aircraft service ceiling is when it can no longer climb at a rate greater than 500 ft/min at full dry power.

 

Best regards,

Tango.

[Buzpilot]

 

I also noticed this chart for the TF-34-GE A-10A engine, only use temperature ranging between 25-50 degree Celisius.

Asuming this is ground or sea level temperatures.

Even a drag index at 8, if the curves are almost linear or continue that direction. It clearly indicate it's possible to fly at Cruise Ceiling (300fpm) above 45,000 feet, already at 15 degree celsius, and even higher at lower temperatures.

Edited September 21, 2012 by Buzpilot

[Yskonyn]

I'm not trying to put out a leg or anything, it's just that this seem to be too stange to be true, compared to everything else i read.

You never tried to reach service ceiling in FC1.12 with the F-15, or you would understand why I'm worried.

And no, I'm not a 'young' padawan, so shut your little mouth!

 

Without trying to de-rail this thread and take it to the personal level; you clearly missed my irony here. :music_whistling:

Touchy Touchy... :joystick:

 

But on topic; the physics modelling of FC is nowhere near advanced enough to compare X vs Y. And like other have pointed out; the info found on wikipedia is often incomplete or out of context, if not plain wrong at other times.

 

It's not a very good case to take this data and then start shouting ED doesn't know what they have been doing with A-10C as it's clearly off in your view. Even take the FC flightmodel to make your point.

They are apples and pears AND the case in point is based on incomplete information.

 

This, coupled with the perceived 'tone' of your message (mainly by claiming something is clearly off) resulted in my reply

 

P.S> You should see my mouth; that would definately prevent you from posting it being little! :D

 

But I digress. :pilotfly:

[Yo-Yo]

 

I also noticed this chart for the TF-34-GE A-10A engine, only use temperature ranging between 25-50 degree Celisius.

Asuming this is ground or sea level temperatures.

Even a drag index at 8, if the curves are almost linear or continue that direction. It clearly indicate it's possible to fly at Cruise Ceiling (300fpm) above 45,000 feet, already at 15 degree celsius, and even higher at lower temperatures.

 

What GW is required for this gest?

And at this chart I can only see temperature deviation from mormal AT THE CERTAIN ALTITUDE. Where did you see absolute values?

[Druid_]

Unfortunately your understanding of the way these graphs are used is wrong.

 

The temp is ISA deviation from standard. The empty weight of the A10 is 29000 so allowing say 1000 lbs of fuel and a drag index of 8 at ISA standard will give a cruise ceiling of 33,500 ft

 

 

 

I also noticed this chart for the TF-34-GE A-10A engine, only use temperature ranging between 25-50 degree Celisius.

Asuming this is ground or sea level temperatures.

Even a drag index at 8, if the curves are almost linear or continue that direction. It clearly indicate it's possible to fly at Cruise Ceiling (300fpm) above 45,000 feet, already at 15 degree celsius, and even higher at lower temperatures.

[Buzpilot]

Without trying to de-rail this thread and take it to the personal level; you clearly missed my irony here. :music_whistling:

Touchy Touchy... :joystick:

 

But on topic; the physics modelling of FC is nowhere near advanced enough to compare X vs Y. And like other have pointed out; the info found on wikipedia is often incomplete or out of context, if not plain wrong at other times.

 

It's not a very good case to take this data and then start shouting ED doesn't know what they have been doing with A-10C as it's clearly off in your view. Even take the FC flightmodel to make your point.

They are apples and pears AND the case in point is based on incomplete information.

 

This, coupled with the perceived 'tone' of your message (mainly by claiming something is clearly off) resulted in my reply

 

P.S> You should see my mouth; that would definately prevent you from posting it being little! :D

 

But I digress. :pilotfly:

I didn't see your irony at all, you just put a lot of comments to make you look smart, without coming with a single fact or comment about the subject at all.

And yes, I'm looking forward to see if FC3 is improved, and my point is if nobody say anything, chances are it will be more like FC2.

[Buzpilot]

Unfortunately your understanding of the way these graphs are used is wrong.

 

The temp is ISA deviation from standard. The empty weight of the A10 is 29000 so allowing say 1000 lbs of fuel and a drag index of 8 at ISA standard will give a cruise ceiling of 33,500 ft

 

Yes, I read the range totally wrong, sorry.

[EtherealN]

And yes, I'm looking forward to see if FC3 is improved, and my point is if nobody say anything, chances are it will be more like FC2.

 

I'm still looking for a concrete example where something is wrong.

[Buzpilot]

I'm still looking for a concrete example where something is wrong.

I guess we have to wait until FC3, to see something concrete.

I don't have TF34-400A sheets.

 

http://www.plane-crazy.net/links/tf34.htm

Edited September 21, 2012 by Buzpilot

[EtherealN]

A-10C uses TF-34-GE-100's, not 400A's. Engine upgrades were planned but scrapped. Please stop using the internet as your source. ;)

 

Okey, but the question is: what is wrong at all? You're saying something is wrong in FC2 (and in DCS A-10C I assume since you spoke of the A-10C?). If you want this fixed with FC3, I'd first need to know what is actually wrong. ;)

 

I will say however that you really should not use Wikipedia as any kind of source for anything related to simulation of the real aircraft. At best it'll give you information that is useless because it's too generalized, but most of the time it'll give you information that is worse than useless through being plain wrong.

Edited September 22, 2012 by EtherealN

[Buzpilot]

A-10C uses TF-34-GE-100's, not 400A's. Engine upgrades were planned but scrapped. Please stop using the internet as your source. ;)

 

Okey, but the question is: what is wrong at all? You're saying something is wrong in FC2 (and in DCS A-10C I assume since you spoke of the A-10C?). If you want this fixed with FC3, I'd first need to know what is actually wrong. ;)

 

I will say however that you really should not use Wikipedia as any kind of source for anything related to simulation of the real aircraft. At best it'll give you information that is useless because it's too generalized, but most of the time it'll give you information that is worse than useless through being plain wrong.

 

I understand the 'internet' is not really reliable, but mostly when it comes to details. So my point is really only that I hope the Jets in FC3 are comparable with the 3.rd party jets, so it could be possible to use most of them online together, instead of risking to have to separate them.

Mainly because the group making FC2 in the past at least, have been very reluctant to do patches at all. But it would be a really nice surprise if they already have done this.

More like a 'heads up' than a bug report, because we don't know what FC3 brings. If jets in FC3 need to have full afterburners on to get up to service ceiling, like in FC2, I would get really disappointed if I bought it, because I really doubt thats reality.

 

Edit;If I remember it wrong I'm sorry, because it's several years since i had FC2 installed now, but from what i recall I needed Full afterburner to reach ceiling.

Edited September 22, 2012 by Buzpilot

[EtherealN]

Buzpilot, FC3 is part of DCS World. Thus, anything done for DCS World is automatically applied to FC3.

 

See the announcement for details.

 

Also, please, at least test your statements before making them. Memory is fallible. If you have documentation for a specific aircraft and don't find it performing according to said documentation in-game, that's good and something we'd all love to see. But please, before you send me on a scurry to test out flight models and dig stuff up from my documentation folder, at least get something more than memories and wikipedia. Case in point being that you have a memory about ceilings, but did not not know how to read the relevant chart when presented with it in this thread? See my point? Thanks. :)

Edited September 22, 2012 by EtherealN

[Buzpilot]

Thanks for pointing out to me that FC3 will have same performance like DCS World

 

Made a test mission, 0 degree Celsius, Winter map.

This track shows the F-15C climb with 500fpm at 59,000 feet, afterburners on, and suddenly stopped climbing at 60,000feet , but waypoint continues to 65,000 feet, if it was a F-16CJ (according to your sheet) it would be able to at least 9,000 feet more, on afterburners, and then, slowly loose climb speed, but not stop there. Not sure what data is on a F-15C with 2 x F-100 engines.

 

If 60,000feet happens to be the Combat ceiling at 0 degree celsius, I asume the 500fpm shouldn't drop to 0 fpm like that.

 

Hope this clears out what I tried to say.

F-15C ceiling.trk

Edited September 23, 2012 by Buzpilot

[Buzpilot]

Buzpilot, FC3 is part of DCS World. Thus, anything done for DCS World is automatically applied to FC3.

 

 

 

Or did you mean to say, that when the F-104C from 3'rd party developers arrives, that broke 100,000 feet altitude, and set new record (in the west). It will be limited to a 50,000 service ceiling barrier in DCS?

Edited September 23, 2012 by Buzpilot

[Tango]

I didn't know there was an altitude limit?

 

Best regards,

Tango.

[159th_Falcon]

Just tested, seems to be an altitude limit in the Mission Editor of DCS World of 20000 meters, regardless of aircraft.

The MIG-25PD is in the ingame encyclopedia stated whit an service ceiling of 24000 meters.

But in the editor limited to 20000 meters.

[Exorcet]

Or did you mean to say, that when the F-104C from 3'rd party developers arrives, that broke 100,000 feet altitude, and set new record (in the west). It will be limited to a 50,000 service ceiling barrier in DCS?

 

100,000 ft can already be reached by every fighter in FC2.

[159th_Falcon]

Errr, no

100 000 feet equals roughly 33 000 km.

 

Highest i have managed to get an SU-33 was angels 13 or 14.

(including some weapons mind you)

[Krebs20]

In dcs world I made a MIG 25 flyable. Needless to say. You can get very high in DCS. 25000 meters and was still climbing fast. There's no roof in DCs as far as I can tell.