>I don't care why they did choose -11's. But It seems EPR>Climb tables are not for -11 engines, also -11's producing>max 14000 lbs thrust right? But Thrust is set to 17000 lbs in>aircraft.cfg ( Correct me if I'm wrong about -11 specs. )>>I wish Ron Freimuth show up and clear our minds :-) For at least the JT8D-9 through -15, improvements in TO thrust rating is due to incremental changes in turbine materials, cooling, etc. That means the higher rated models can tolerate high TO EPR, N1, and EGT. So the "Flight 1/Dreamfleat 727" has any one of those turbines models you want to assume it has. I think the TO, Climb, and Cruise tables are for a -11 (or -9). For the most part, only TO settings vary, the same climb and cruise settings are used for any of the mid-range models. The '17000 lb' thrust set in aircraft.cfg is not the rated TO thrust. That was set so SL TO thrust would be correct relative to N1, N2, and EPR. Regardless, there isn't much difference in TO thrust:JT8D-11 15,000 lb 5 min JT8D-7B SLST: 14,000 lb 5 min,12,200(12,500) contJT8D-16: 16,000 5 min I don't have the corresponding SL TO EPR, N1 handy, but increasing N1 by 1% increases Thrust by about 3%, so 1% higher would give about the rated TO thrust for a -15 relative to a -11. I do know setting N2 to 94.0% will give 15,000 lb TO trust at SL, 15C. Appropriate for the -11. Red line RPM limits are the same for all these models, a bit over 100%. Generally something else sets the actual limit, depending on conditions. N1, N2, EPR, and EGT are accurate, so if you set N1 to the appropriate TO value for any of the models in the above range, you will get the thrust you should. Check with AFSD if you like. ;) AC/Bleeds also affect how high one can set N1/EPR. On hot runways, EGT may be the limiting factor. As with the EPR gauge, EGG is calculated independently of the poor MSFS variables. TAT is important as far as how high N1/EPR can be set. One would do well to print out the manual's tables showing maximum N1/EPR as a function of FL and TAT. That is, if you want to fly like a pro. ;) 'Flight with Unreliable Airspeed' is also useful. It gives EPR,N1, Pitch, etc for many ISA flight conditions. I noted an error in the Descent pitch (should be corrected in the future). Pitch Weight 1 deg 'high' 0 'mid' 2 'low' That should be -2 deg. I've found pushing the nose down to -1 deg or so after dropping N1's to 55% gives about the right pitch for descent. Ron

Nevermind, found it.

I just wanted to say thank your team for a great aircraft! Definately my favorite.. and I have purchased a few planes. It has basically every system at your fingertips including wipers, and smooth framerates, the important things! Being a freighter dog this plane is perfect. Thanks again, and hopefully there will be more freighter repaints in the future possibly?

I simply cannot believe how long this thread has become over what is truly a trivial issue.Had Dreamfleet simply listed the engine type as a -15 I'd wager that no one would have known any differently.This reminds me of a post from several years ago where someone went nuts over the total number of rivets a painter had used on a wing texture. "That wing is SUPPOSED to have 4,321 rivets, and you only put 4,313 on it!" :)

>I simply cannot believe how long this thread has become over>what is truly a trivial issue. Actually, the variations in the JT8D turbines wasn't trivial for me. Eventually I found that all but the the -17 (and perhaps -7) had identical thrust vs N1 curves. One FM cruise table noted "all versions". Only TO settings would vary between engines, higher N1 for higher TO rated units. I think the FM cruise tables were based on acceptable settings regardless of what turbines a specific 727 might have. To keep from confusing the flight crews. I also found that the original 727's used -7 turbines. But, it appears the -9 was available and shipped with even early production models. Some of the FM tables I looked at were apparently for the -7 or -9. A cruise table headed with 'all versions' apparently applied to -9 and up. And, allowed Mach 0.80 cruise at some temperatures the earliest versions couldn't handle. Regardless, FM tables can vary between airlines. Typically they are derated a bit from the P&W limits. In order to get longer MTBO's. If you can't get the Mach you want using the tables in the manual, turn off bleeds and AC. Then, you can increase EPR/N1 a bit and still be within the table limits. Let the passengers sweat. ;) Also, note #2 turbine can be set 0.02 higher in EPR for TO. Perhaps even a bit more in climb and cruise. BTW, Mach 0.80 is normally the highest speed used. One source mentioned 'use Mach 0.82 only if need to make up time'. FS fuel is cheap, so burn all you want. You can refuel in flight if you have to. ;) If you want to fantasize even more do it in your dreams. Ron

Well Bill sir I asked a legit question, it's true a few took this the wrong way and was not my intention. The gist still holds correct though and I stand by the facts. Engine TYPE and RIVETS do not rate on the same page in my book. AGAIN I already said it was *trivial* in this I mean that DF have offered a engine that represent the 727 good enough and pretty #### good right out of the gates. I bought it and loved it the moment I started it up, this has not changed....Best Wishes,[h4]Randy J. Smith[/h4]http://www.rawbw.com/~bdoolin/shinault/southparkcartmad.gif[h3]PMDG 747![/h3]Caution! Not a real pilot, but do play one on TV ;-)ASUS KV8 DLX | AMD 3200 64 | 1 GIG PC 3200 DDR | GIGABYTE 5700 ULTRA | ViewSonic VP192b 19" |

Ron, thanks for reply.As I said before, I don't care why it's -11 instead of -15, -17 etc.The Important thing is how to operate this engines properly. Is the tables included in manuals for Model -11 engines? The reason because I'm asking this somehow they are not working for me. Climb EPR tables seems a bit off. Takeoff with 2.00 Epr than just after passing 5000 feet while TAT is dropping quickly, I found 2.1, 2.2 EPR in the table for climb. It's okay with EPR gauge but N1 is way to high. May be it's just me because I'm a N1 guy, takeoff with ~%90 N1 then Climb with ~%100 N1 doesn't seem correct to me, or correct me please :)To get High EPR (2.2, 2,4) values, especially at high altitudes I have to firewall throttles, sometimes even firewalled throttles doesn't give 2.2+ EPR at high altitudes ( 20.000 feet and above )( Closing AC packs is ok with Cargo Planes but what about Passanger jets? )And for the cruise, both M.78 and M.80 cruise tables always giving me at least .2 more speed. ( I'm using only -200 Cargo model with 135.000 Lbs ZFW with typicall cruise GW about 155.000 lbs.)Ron, I understand you put your talent and time specially for EPR modelling. But I can't use it with this tables.. Please help.

MaxThrust:Just a tad bit of insight on the AC pack question. When you are climbing out the FE will generally keep an eye on the temps and as soon as the bleed air gets cold enough there is no longer a need for the AC packs to be running anyway. Unless you are going supersonic whereby heating the surface of the aircraft, there is no need for air-conditioning. As for the -11 question raised by others, I asked myself the same thing but I also answered myself in the same breath - who the *&^% cares. I fly RW -27's and can find many items to question but added all together, they are so miniscule compared to the overall package that again, I answered myself with who the *&^% cares.I fly a 727 with

>Ron, thanks for reply.>>As I said before, I don't care why it's -11 instead of -15,>-17 etc.>>The Important thing is how to operate this engines properly.>Is the tables included in manuals for Model -11 engines? The>reason because I'm asking this somehow they are not working>for me. Climb EPR tables seems a bit off. Takeoff with 2.00>Epr than just after passing 5000 feet while TAT is dropping>quickly, I found 2.1, 2.2 EPR in the table for climb. Climb EPR with a standard atmosphere should be more like 1.85 below 10,000 ft. That is, drop EPR to 1.85 or so within five minutes. In fact, one can generally drop to 1.85 in a couple of minutes, even lower to keep from climbing too fast at lighter weights. TAT is always higher than SAT, SAT would be about -5C at 10,000 ft, but TAT would be quite a bit higher, even at 250 kts IAS. Unfortunately, one has to sit in the First Officer's side to see the TAT gauge (or, use the VC); and the #3 engine gauges. I've seen tables based on SAT and IAS/Mach. TAT is worked in for the maximum ratings with them. As one accelerates above FL 100, IAS should be increased to about 290 kts. The -100 likes 10 kts higher -- it has less drag, so one can climb at a faster IAS and still have efficient fuel consumption. Anyway, the higher IAS above FL 100 further increases TAT. SAT is decreasing, but TAT may stay about the same for a while. I remember that one can increase EPR as FL increases (or, it increases automatically with a constant throttle setting), assuming one has accelerated to climb IAS/Mach above 10,000 ft. To 2.0 or higher above FL 300. Cruise EPR runs near 1.86 at Mach 0.80, when weight is near 160,000 lb. Lower at lower weights. Non standard SAT changes things. >It's>okay with EPR gauge but N1 is way to high. May be it's just me>because I'm a N1 guy, takeoff with ~%90 N1 then Climb with>~%100 N1 doesn't seem correct to me, or correct me please :) Something is wrong, Generally, N1 should never exceed 94%, while 90% is more typical of climb ratings. Cruise runs more like 87%, depending on weight an FL. >To get High EPR (2.2, 2,4) values, especially at high>altitudes I have to firewall throttles, sometimes even>firewalled throttles doesn't give 2.2+ EPR at high altitudes (>20.000 feet and above )>( Closing AC packs is ok with Cargo Planes but what about>Passanger jets? ) I've been scanning through a bunch of 727 FM tables, but don't have the more complete tables in the DF manual in front of me. I see 'Maximum Cruise EPR' 2.07 at FL 350, TAT = -20 C. JT8D model not specified. However, I expect it's for a -11 or higher, the date on that page is 1994. 2.07 would be more than enough to get to Mach 0.82, I've rarely seen EPR above 2.0 in cruise. And, I normally flew near 160,000 lb. Only when the air is significantly colder than normal does one ever get to the higher EPR's. I wrote something on flying the 727, including approximate EPR's from TO to climb to cruise. I'll try to clean it up a bit and post it. Ron

I don't see why everyone is attacking Randy for his OPINIONS. Yes, its a trivial issue...he's already admitted that. But that doesn't mean that it doesn't warrent respect and discussion.>>>>Had Dreamfleet simply listed the engine type as a -15 I'd wager that no one would have known any differently.<<<

that there's no hushkit on them...Or no winglets.Or that the seats in the cabin are the wrong shade of green under certain light conditions.

Anthony, Bill Leaming is known for speaking his own views on many subjects and they should be taken as just that....his own views.As to the banner, I have no idea why he used it here but it should have been left out.I must say that Bill's comments seem to be rhetorical in nature so that may be what has caused some consternation here. Bill Leaming is not now,nor has he ever been a spokesman for Eaglesoft Development Group.Your question: >Does Eaglesoft actually release false information to the public about its addons in the interest of getting more sales? How can you condone or support such a practice?Thanks also to the Eaglesoft team for (hopefully) remaining honest.

Ron, I must thank you again for answering my questions even with this nonsense arguements going on.So far I learned Climb EPR should be ~1.85 below FL100 and then never exceed %94 N1 while climbing with 290kts.I'm lookig forward to your "Flying the 727" document, thank you.Regards,Bozhan

Usually DF and F1 get data from an aircraft operator (and whenever available use an original aircraft as much as possible) to get the data needed.

*Goes and gets a fresh bowl of popcorn*:)