Another Project .... "ON THE GO" At The Moment
Oct 26, 2016 3:54:59 GMT
aerofoto - HJG Admin and gus like this
Post by aerofoto - HJG Admin on Oct 26, 2016 3:54:59 GMT
A little while ago .... actually it was a fair way back .... Mike, and myself, were messing around with the B707/B720/C135 FDE's .... intending to try'n improve their AOA/pitch attitude during approach to landing in particular.
Whilst this has "never" really been a major problem .... we were still of the opinion that these simulations were "in need of" improvement in this respect hence our deciding to "fiddle with things", but, as often becomes the case "HERE" (at HJG) .... this particular project was/had to be "set aside" (it wasn't something of any great urgency) in order for us to be able to accomodate other projects, of greater priority, and which have since been released.
Even now .... we're working this "in-between" other projects and only as time permits.
ANYWAY .... here's a brief report in regard to what we've achieved, so far, and are continuing to try'n do ....
Let me start by saying that any simulation can fly well, or badly, depending upon how it's flown to start with.
HJG simulations fly best in accordance with the "basic" flying guides we publish as part of our forum based Panel Installation & Handling Notes/Manuals. Whilst some of the information contained within these guides might not be truly reflective of the real world procedures used to fly any particular aircraft type .... this data "is always" written around how any particular simulation "wants to fly" .... and/or .... "can be made to fly" in FS .... this being about "AS REAL AS IT GETS" remembering the old MSFS product marketing tag/legend.
Most of the HJG B707/B720/C135 simulations have always been pretty good during T/O, climb, cruise, and descent .... "provided they're flown properly (not overweight in particular .... do that and no simulation will work properly regardless of what it is) to start with", but, during approaches to landing .... and even with less than 20% total fuel load remaining (as would normally be the case upon the conclusion of any flight) .... and with a full payload also .... the AOA/nose pitch attitude of these simulations "did" exceed what we'd normally like to see .... and .... the only way to address this, to some extent (without the benefit of FDE editing we're currently working on), has been to fly the approach to landing faster than should be the case, in order to try'n encourage the AOA/nose pitch attitude to "reduce somewhat" (aided by flap influence) during the approach to landing.
Given a number of specific CFG edits which we've been trialing .... aided by assistance from another trusted and "technically competent" community forum member/supporter also .... we feel we've more-or-less found the "sweet spot" in order to be able to greatly improve the natural approach to landing attitude/behaviour of most of the HJG B707/B720/C135 simulations .... as the following images (using our B707-320B ADV in this particular case) may/should illustrate ....
FL310 cruise .... MACH 0.81.2, IAS 310 KTS, TAS 476 MPH .... EPR 1.42, N1 84 %, EGT, 406*C (degrees), N2 87 % .... AI PITCH ATTITUDE +1* (degree) .... not all of these numbers are actually relevant (they "DO" also differ for each B707/B720/C135 simulation too in accordance with their simulated weight, engine thrust, altitude, and other aerodynamic representations anyway .... which, once again, differ considerably among these aircraft type simulations), but, these figures do give some idea of performance for the indicated parameters, and which are about as good as it gets, or rather, as fine as we can make it, in FS, and for this particular simulation .... the "B707-320B ADV" ....
AI PITCH ATTITUDE +1* (degree) during the high altitude/high speed cruise regime ....
Approach to landing .... less than 20% total fuel remaining (this detail's critical for any simulation and not just the HJG B707's since if one's too heavy the nose "WILL" tend to remain high) .... full flaps .... gear down .... 5 DME from the RWY threshold .... passing through 1,500 FT on the RA .... 135 KIAS .... with an approximetly + 1 AI pitch attitude ....
Approach to landing .... full flaps .... gear down .... less than 2 DME from the RWY threshold .... passing through 250 FT on the RA .... 132 KIAS .... and maintaining an approximetly + 1 (degree) AI pitch attitude prior to landing ....
The flair to touch-down .... AI pitch attitude increasing to approximately +2 (degrees) .... and engines spooled back prior to landing/"hitting the ground"
SO THEN .... and as should be evident above .... "QUITE AN IMPROVEMENT" so far
That's where we're at .... for the moment.
Flying the B707's/B720's/C135's the following factors must/should always be born-in-mind too ....
- Never attempt any landing with in excess of 20% total fuel remaining .... at the very most.
- These B707's/B720's/C135's "are not" good at flying an AP controlled ILS/GS coupled approach to landing .... and aren't meant to be (given that these aircraft represent old technology from a time when ILS was in it's infancy .... they're not AIRBUSES remember), so, the ILS/GS indications, whilst featured (as it was on later versions of these aircraft anyway) should be used as "a guide only", but, all approaches to landing are best flown "manually" .... similar also applies to the CV-880, CV-990, and DC-8 simulations and for the same reasons.
- Extending the flaps and landing gear "at the right airspeed" .... whilst also managing engine power sensibly, and with anticipation, in order to nail the right approach to landing airspeed and ensure the desirable pitch attitude (not quite as easy as it sounds, but, practice does make perfect) is critical to maintaining a good, and stable, approach to landing (always try'n stay in front of whatever's happening) .... OR .... the simulation can, and probably will, depart, very easily from control
Each of the above recommendations apply regardless whether or not these FDE's are updated.
When the time comes we'll either post the necessary CFG edits, for everyone (whom wants to) to update there own CFG's .... "once we're (first) entirely satisfied with the results" .... OR .... we may be looking at a B707/B720 Aircraft Base Pack update in the not too distant future .... I'm not sure which at this very early stage.
It's perhaps needless for me to say ..... but .... this particular project, like all HJG projects, will continue to be advanced between "other priorities" and as personal time permits .... of course
Mark C
AKL/NZ
Whilst this has "never" really been a major problem .... we were still of the opinion that these simulations were "in need of" improvement in this respect hence our deciding to "fiddle with things", but, as often becomes the case "HERE" (at HJG) .... this particular project was/had to be "set aside" (it wasn't something of any great urgency) in order for us to be able to accomodate other projects, of greater priority, and which have since been released.
Even now .... we're working this "in-between" other projects and only as time permits.
ANYWAY .... here's a brief report in regard to what we've achieved, so far, and are continuing to try'n do ....
Let me start by saying that any simulation can fly well, or badly, depending upon how it's flown to start with.
HJG simulations fly best in accordance with the "basic" flying guides we publish as part of our forum based Panel Installation & Handling Notes/Manuals. Whilst some of the information contained within these guides might not be truly reflective of the real world procedures used to fly any particular aircraft type .... this data "is always" written around how any particular simulation "wants to fly" .... and/or .... "can be made to fly" in FS .... this being about "AS REAL AS IT GETS" remembering the old MSFS product marketing tag/legend.
Most of the HJG B707/B720/C135 simulations have always been pretty good during T/O, climb, cruise, and descent .... "provided they're flown properly (not overweight in particular .... do that and no simulation will work properly regardless of what it is) to start with", but, during approaches to landing .... and even with less than 20% total fuel load remaining (as would normally be the case upon the conclusion of any flight) .... and with a full payload also .... the AOA/nose pitch attitude of these simulations "did" exceed what we'd normally like to see .... and .... the only way to address this, to some extent (without the benefit of FDE editing we're currently working on), has been to fly the approach to landing faster than should be the case, in order to try'n encourage the AOA/nose pitch attitude to "reduce somewhat" (aided by flap influence) during the approach to landing.
Given a number of specific CFG edits which we've been trialing .... aided by assistance from another trusted and "technically competent" community forum member/supporter also .... we feel we've more-or-less found the "sweet spot" in order to be able to greatly improve the natural approach to landing attitude/behaviour of most of the HJG B707/B720/C135 simulations .... as the following images (using our B707-320B ADV in this particular case) may/should illustrate ....
FL310 cruise .... MACH 0.81.2, IAS 310 KTS, TAS 476 MPH .... EPR 1.42, N1 84 %, EGT, 406*C (degrees), N2 87 % .... AI PITCH ATTITUDE +1* (degree) .... not all of these numbers are actually relevant (they "DO" also differ for each B707/B720/C135 simulation too in accordance with their simulated weight, engine thrust, altitude, and other aerodynamic representations anyway .... which, once again, differ considerably among these aircraft type simulations), but, these figures do give some idea of performance for the indicated parameters, and which are about as good as it gets, or rather, as fine as we can make it, in FS, and for this particular simulation .... the "B707-320B ADV" ....
AI PITCH ATTITUDE +1* (degree) during the high altitude/high speed cruise regime ....
Approach to landing .... less than 20% total fuel remaining (this detail's critical for any simulation and not just the HJG B707's since if one's too heavy the nose "WILL" tend to remain high) .... full flaps .... gear down .... 5 DME from the RWY threshold .... passing through 1,500 FT on the RA .... 135 KIAS .... with an approximetly + 1 AI pitch attitude ....
Approach to landing .... full flaps .... gear down .... less than 2 DME from the RWY threshold .... passing through 250 FT on the RA .... 132 KIAS .... and maintaining an approximetly + 1 (degree) AI pitch attitude prior to landing ....
The flair to touch-down .... AI pitch attitude increasing to approximately +2 (degrees) .... and engines spooled back prior to landing/"hitting the ground"
SO THEN .... and as should be evident above .... "QUITE AN IMPROVEMENT" so far
That's where we're at .... for the moment.
Flying the B707's/B720's/C135's the following factors must/should always be born-in-mind too ....
- Never attempt any landing with in excess of 20% total fuel remaining .... at the very most.
- These B707's/B720's/C135's "are not" good at flying an AP controlled ILS/GS coupled approach to landing .... and aren't meant to be (given that these aircraft represent old technology from a time when ILS was in it's infancy .... they're not AIRBUSES remember), so, the ILS/GS indications, whilst featured (as it was on later versions of these aircraft anyway) should be used as "a guide only", but, all approaches to landing are best flown "manually" .... similar also applies to the CV-880, CV-990, and DC-8 simulations and for the same reasons.
- Extending the flaps and landing gear "at the right airspeed" .... whilst also managing engine power sensibly, and with anticipation, in order to nail the right approach to landing airspeed and ensure the desirable pitch attitude (not quite as easy as it sounds, but, practice does make perfect) is critical to maintaining a good, and stable, approach to landing (always try'n stay in front of whatever's happening) .... OR .... the simulation can, and probably will, depart, very easily from control
Each of the above recommendations apply regardless whether or not these FDE's are updated.
When the time comes we'll either post the necessary CFG edits, for everyone (whom wants to) to update there own CFG's .... "once we're (first) entirely satisfied with the results" .... OR .... we may be looking at a B707/B720 Aircraft Base Pack update in the not too distant future .... I'm not sure which at this very early stage.
It's perhaps needless for me to say ..... but .... this particular project, like all HJG projects, will continue to be advanced between "other priorities" and as personal time permits .... of course
Mark C
AKL/NZ