A little F-15C AFM update - 7 December 2013

LOL, yep only saw one in Holloman while working on the stink bug, They used it in Phase doc, IIRC.

I honestly don't recall seeing an electric mule at all (just over 19 years now, damn I'm getting old).

Aerodynamics

Hi everyone,

Separate calculations of aerodynamics characteristics are performed for each of the above named components in the entire range of local angles of attack and sliding (including super-critical), local dynamic pressure and Mach number taking into consideration deviation and grade of destruction of control instruments and some airframe components.

I'm struggling to understand (and then, translate into French) what sliding means in the above quote (excerpt from one of Wags'recent announcements). :huh:

As it's paired with "(including super-critical)" I wonder if it's not about the airflow (which, in a way, slides along the airfoils)?

Is it possible that the original definition was in Russian, and that it "took a hit" during an approximate translation into English?

Or OTOH is my English that rusty? (it may be... :D)

Thanks in advance for any help on that matter. :thumbup:

Cheers

Az'

I think it's because it is probably translated from Russian to English, so I think Yo-Yo would be the best person to clarify here :)

Hi everyone,

 

 

 

I'm struggling to understand (and then, translate into French) what sliding means in the above quote (excerpt from one of Wags'recent announcements). :huh:

As it's paired with "(including super-critical)" I wonder if it's not about the airflow (which, in a way, slides along the airfoils)?

 

Is it possible that the original definition was in Russian, and that it "took a hit" during an approximate translation into English?

Or OTOH is my English that rusty? (it may be... :D)

 

Thanks in advance for any help on that matter. :thumbup:

Cheers

Az'

Hello Az',

I think 'sliding' simply means 'including' in that sentence hence explained in between brackets right away.

Here is a go in French : " Le calcul des caractéristiques aérodynamiques est effectué de façon séparée pour chaque composant cité plus haut en rapport avec l'angle d'attaque local et super-critique, la pression dynamique locale et la vitesse en Mach, le tout en prenant en considération la déviation ainsi que les dégâts causés aux surfaces de contrôle ainsi qu'au fuselage."

Hi Flankerator,

Thanks for your reply.

I disagree: "including" is written, yes, but sliding is, too.

The construction of the sentence makes me feel like there are 2 things : AoA and "sliding" (?), the latter having the property of possibly being super-critical.

I just asked a girl at work, who is Ukrainian. She doesn't know anything about flying, but said обтекание could be translated by sliding. обтекание being associated with a flow (water, sand... or air!) is correct, she said. Perhaps that was the original word?

Cheers,

Az'

I'd say "скольжение" would be the proper translation - it's what you do when you are ice skating, or when you brake your car on an icy road and instead of stopping it "скользит" slides before it stops.

Keep an eye on that Ukrainian - Ukrainian girls are the best ;-)

P.S. I think in this particular context sliding could mean slip - like the slip indicator in Uh-1H

Did he really say that it will be included with 1.2.8? ;)

No, but if Wags said it's unrealistic to squeeze F-15C AFM into 1.2.7 than 1.2.8. is my logic.

I believe it was stated it would not make it into the 1.2.7 Update.

however it was never said it was delayed completely until 1.2.8.

As there are usually multiple smaller updates for each main version.

Sliding for 'glisser', so probably here you can interpret it as 'déraper.' It follows Gloom Demon's opinion.

Both gliding and скольжение mean 'déraper' (even though скольжение is a name and not a verb) :)

Edit:

La composante Pa du poids est décalée vers l’extérieur du virage, il s'agit alors d'un dérapage. Le poids apparent n'est plus contenu dans le plan de symétrie, il est à l'extérieur du virage. La demi-aile extérieure au virage subit une portance plus importante, ce qui entraîne une tendance supplémentaire à l'inclinaison du virage et, l'avion a une forte tendance à piquer, on dit qu'il s'engage

.

Il s'agit d'un équilibre instable, le mouvement ayant tendance à s'accroître pour entraîner finalement un décrochage dissymétrique brutal de la demi aile intérieure et un

départ en vrille

And I am not as sure about the next comment, but I think it should be translated with the verb 'to skid' in english ;)

Well, in fact I've thought about "déraper" (to slip).

But I've never heard about super-critical slipping. Hence my doubts.

Like Tharos said, it would be nice if Yo-Yo could set it straight :)

I believe it was stated it would not make it into the 1.2.7 Update.

 

however it was never said it was delayed completely until 1.2.8.

 

As there are usually multiple smaller updates for each main version.

Although this is not certain, it is good to know that there is that possibility of making it in a smaller update.

From the Belsimtek website:

"The estimated release date for the advanced flight model for F-15C Eagle DCS module is middle of 2014"

Here is the link. I hope that information is old. I really do. Otherwise Im a sad panda. :(

http://www.belsimtek.com/news/217/

From the Belsimtek website:

 

"The estimated release date for the advanced flight model for F-15C Eagle DCS module is middle of 2014"

 

Here is the link. I hope that information is old. I really do. Otherwise Im a sad panda. :(

 

http://www.belsimtek.com/news/217/

I saw what equated to a post date of early October on this, but I dont know how much could have change as far as a projected release from that time til now. I thought we were close but it is what it is.

They are calling it DCS: F15C module...

Given that the full clickable cockpit etc is still under consideration I feel this would negate the purpose of the true DCS title. (DCS being full on, 6DOF, AFM, full systems etc..)

Now that's depressing :(

Regards

Now that's depressing :(

 

Regards

And me thinking I was being reasonable expecting it to be released on March 2014... but middle of the year? :cry:

Don't jump to any conclusions yet. Nothing is written in stone.

Original (deleted) annoucement stated that AFM might be ready by the end of November, Wags now said they need some more time for tuning since they have actual eagle driver testing it. I doubt that "tuning phase" will last for another 6 months or so. Also, we had AFM landing video 2 months ago.

Drop all else. WWII stuff, Nevada Map, who knows what else...

I know there is parallel work going on at the same time, but when you release news, or actually release new product before a DCS Fighter jet, it feels like the fans that flew Lockon, that invested all theat time and money for all those years are being pushed to the back of the line.

Work on DCS level fighter jet first :(

Have you read this:

"Actual VLE on a "clean" F-15E is 300 KCAS, but with the LANTIRN pods hanging under the jet, the disturbed airflow buffets the gear doors and reduces VLE to 250 KCAS."

Source: http://www.warbirdaeropress.com/articles/F15/F15%20Pt%201.htm

I know it's not related to the F-15C AFM but I thought the story behind the link worth the read. (Sorry if it could be considered as 'parasiting'/'polluting' the thread)

Anyway, the reason of the post:

They are calling it DCS: F15C module...

 

Given that the full clickable cockpit etc is still under consideration I feel this would negate the purpose of the true DCS title. (DCS being full on, 6DOF, AFM, full systems etc..)

Wouldn't the module be called/released as "DCS Flamming Cliffs: F-15C"?

But it's stated: "We are considering the possibility of creating a complete avionics model with clickable cockpit and accurate systems modeling. This would be a major development however, so a final decision has not yet been made." (Source: http://www.belsimtek.com/news/217/)

In that case, the title would 'merit' its DCS: F-15c title, don't you think? (just add the accurate hydraulic system, electrical systems,... and we're good.)

EDIT: Concerning the development of the F-15C AFM, "The flight model has been through over eight months of development and is now undergoing initial external (closed beta) testing. " (Source: http://www.belsimtek.com/news/217/)

8 Month!

They are calling it DCS: F15C module...

 

Given that the full clickable cockpit etc is still under consideration I feel this would negate the purpose of the true DCS title. (DCS being full on, 6DOF, AFM, full systems etc..)

Wouldn't the module be called/released as "DCS Flamming Cliffs: F-15C"?

Probably just an error.

A proper DCS F-15C Eagle probably won't happen. Belsimtek have the F-86 & AH-1G coming in the first half of 2014 so until then they have there hands full, and ED have too much on their plate too.

Probably just an error.

This.

A proper DCS F-15C Eagle probably won't happen.

That is to be seen.

From the Belsimtek website:

 

"The estimated release date for the advanced flight model for F-15C Eagle DCS module is middle of 2014"

 

Here is the link. I hope that information is old. I really do. Otherwise Im a sad panda. :(

 

http://www.belsimtek.com/news/217/

Hi VaniaB :)

First, thank you, because this from your link:

The complete aerodynamics model accounts for the entire spectrum of mass, force, and moment interactions of the aircraft as a physical object subjected to airflow.

... pretty much answers my question from post #112, in confirming that airflow is taken into account when calculating AFMs. Nice one :thumbup:

Secondly, about the estimated release date you quoted: well, it's an estimate. And because Belsimtek's article talks about "DCS: F-15C Eagle" (not "F-15C: DCS Flaming Cliffs"), "advanced flight and engine models" and "new flight and related component models", I would go as far as to guess there are 2 things here:

• a first "basic" version of the F-15 AFM, for Flaming Cliffs 3 and the to-be-released-soon F-15C: DCS Flaming Cliffs.
  
• then, a much more complete F-15 AFM, with all the bells and whistles (*), which may not be ready before middle 2014, and is intented for the later-coming "hardcore" (à la A-10C) module DCS: F-15C.

(*) Remember Wags'post:

This is the basic definition, but not limited to, what we use to define a DCS aircraft with an AFM. Further detail can be added to include dynamic engine operation, sub-system modeling, fluid dynamics, and damage modeling. (...) As such, the definition of an AFM can be a bit broad and encompass products ranging from the the Su-25T to the A-10C.

Cheers,

Az'

PS: If I'm wrong, and indeed the ~release of the F-15's AFM is middle 2014... well, it's "only" 6 months from now.