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Delta DC-9's

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"Handheld GPS" units aren't certified for use in Part 121 airline service.
 
Fubijaakr said:
"Handheld GPS" units aren't certified for use in Part 121 airline service.
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but they can be used for advisory information, such as my ground speed is 413 kts and I will reach BOZST at 0412
 
I assumed he meant for navigation.
 
Just VOR DME (rollover). Some of the VORs seem pretty bad too (badger for example), so if you look at a 9 track on flightaware, its a bit wavy ;). We use forecasted winds for descent planning, and get told to go direct to intersections but we are used to it..
 
airplane wizard said:
Do you Dc-9 guys/gals ever use a handheld GPS for a backup while flying, or just the good old VOR/DME?
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I have never seen anyone with a GPS. It could very quickly become a distraction, you are already so busy up there. Everything is pretty much SWAG, emphasis on the science part. I actually have a 8" descent computer (similar to an E-6B) that was once standard issue. After several years on the airplane, you know what works. One of the harder things to get adjusted to when flying the DC-9 is that I can't be as precise as I was in previous aircraft. That being said, I turn being as precise as possible into part of the challenge of flying the airplane. You just really have to stay on your game, it is easy to get behind very quickly if you forget to turn, level off, or start that descent. In practice, this just means constantly doing the math on the way down, and adjusting as necessary to stay on profile. Sometimes that means that you started down too early, but if they were that concerned with it, we would have more precise equipment.

I'm glad I got to fly it, but I won't miss 5 leg days in July, especially that they all have to be through ATL now.

Delayed
Every
Leg
Through
Atlanta
 
Gorditas said:
I have never seen anyone with a GPS. It could very quickly become a distraction, you are already so busy up there. Everything is pretty much SWAG, emphasis on the science part. I actually have a 8" descent computer (similar to an E-6B) that was once standard issue. After several years on the airplane, you know what works. One of the harder things to get adjusted to when flying the DC-9 is that I can't be as precise as I was in previous aircraft. That being said, I turn being as precise as possible into part of the challenge of flying the airplane. You just really have to stay on your game, it is easy to get behind very quickly if you forget to turn, level off, or start that descent. In practice, this just means constantly doing the math on the way down, and adjusting as necessary to stay on profile. Sometimes that means that you started down too early, but if they were that concerned with it, we would have more precise equipment.

I'm glad I got to fly it, but I won't miss 5 leg days in July, especially that they all have to be through ATL now.

Delayed
Every
Leg
Through
Atlanta
Click to expand...

Does the descent computer just tell you how far out (nm) to start descending using groundspeed and how high you are or is it more that that?
 
737 said:
Brings back memories of the 737-200. 2 VORs, DME and the Nav aid of the future ADF!
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They should bring back the ADF's. Funny how many ga pilots can't/don't want to do use them. I never had too much trouble with them and was the only thing I did right on my first IFR checkride. Of course the pros never have any trouble with them right???
 
airplane wizard said:
Does the descent computer just tell you how far out (nm) to start descending using groundspeed and how high you are or is it more that that?
Click to expand...

We don't have any actual ground-speed readout. It is purely based on zero wind conditions, mileage, and 6-1 above FL290, and 3-1 below. You have to make adjustments based on wind. There are several scales on it for -30/-40 series A/C (all retired last year) -50 series A/C, and with wing A/I on. (needing some power in the descent) It is double sided with inner and outer scales. Honestly, the people who came up with devices like these amaze me. Getting a purely mechanical device to do precise calculations is a pretty neat feat.
 
Gorditas said:
Getting a purely mechanical device to do precise calculations is a pretty neat feat.
Click to expand...

Speaking of neat feats...the first time I sat in the 717 I gazed in puzzled amazement at the utter complexity of the window mechanism for a good five minutes. I'm still in awe of the engineers who created that contraption.
 
Having never flown the 9 (lots of hours in jumpseat), I always thought the wiz wheel thingy was a little overkill. Why not just use 3:1 and adjust for wind like almost every other plane.


Gorditas said:
We don't have any actual ground-speed readout. It is purely based on zero wind conditions, mileage, and 6-1 above FL290, and 3-1 below. You have to make adjustments based on wind. There are several scales on it for -30/-40 series A/C (all retired last year) -50 series A/C, and with wing A/I on. (needing some power in the descent) It is double sided with inner and outer scales. Honestly, the people who came up with devices like these amaze me. Getting a purely mechanical device to do precise calculations is a pretty neat feat.
Click to expand...
 
Cobraair75drvr said:
Having never flown the 9 (lots of hours in jumpseat), I always thought the wiz wheel thingy was a little overkill. Why not just use 3:1 and adjust for wind like almost every other plane.
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3:1 doesn't work on the -9. To hold pressurization while descending aboving FL290, you can't go to flt idle. Only flt idle below FL290, and then it's 2:1.
I thought the same thing when checking out on it, but 3:1 really doesn't work...on -9.
 
IF you need to GPS to fly a DC-9, you won't be flying the DC-9. Easiest jet to manage IMO. 6 to 1 from 350-290, 2 to 1 to 10k, 3 to 1 10k and below plus the fudge factor. Used speedbrakes once a month if I was yackin. Bye Bye DC-9
 
Coolest DC9 feature...the over the shoulder compass and mirror combination. The mirror comes in handy for checking out chicks
 
nwaf16dude said:
Coolest DC9 feature...the over the shoulder compass and mirror combination. The mirror comes in handy for checking out chicks
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When I checked out on the -88 I thought they were pulling my leg when they told me that the compass was behind me and I had to use a mirror. How did that ever get certified???

Same way with the lie flats on the 777. The first time I sat in first and the FA came over before landing and said my seat wasn't erect enough for my airbag to deploy, I about laughed her off the jet thinking she was being funny. I didn't think anything more about it until we got the lie flats on the ER several months later and watching the training videos - there sure are airbags!
 
So, how do you figure out what rate of descent you need for a 3:1 or 2:1 ratio? I heard a rule of thumb of altitude*3 gives you how far out in nm to start down??
 
If I'm at FL330 and get cross TWINS at 110 and 250 you get this: (6 to 1)
330 - 290 = 4000 .. 4 * 6 = 24 miles. ; (3 to 1) 290 - 110 = 18000 ... 18 * 3 = 54 miles . ; 24 + 54 + 4 (for slow from 300 to 250) - 10 (for avg 50kt headwind for example) equals 72 .... So start descent 72 miles from twins.. (some guys may use 2 to 1 but I think 3 works better for the diamond elite HVC happiness)
Oh .. And do that every few thousand feet on the way down to check progress ;)


Edit: oh and if you are in icing conditions or anticipate it, that changes things too
 
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I do miss flying the DC9 just not the 5 leg days. Very enjoyable plane to fly, of course I have a couple thousand hours 121 in airplanes without autopilot ie Jetstream 32 and BE1900.

Best placard I had in an airplane was in the BE1900C, on the attitude indicator it said "Pull for quick erect" probably would work...
 
Rough67 said:
If I'm at FL330 and get cross TWINS at 110 and 250 you get this: (6 to 1)
330 - 290 = 4000 .. 4 * 6 = 24 miles. ; (3 to 1) 290 - 110 = 18000 ... 18 * 3 = 54 miles . ; 24 + 54 + 4 (for slow from 300 to 250) - 10 (for avg 50kt headwind for example) equals 72 .... So start descent 72 miles from twins.. (some guys may use 2 to 1 but I think 3 works better for the diamond elite HVC happiness)
Oh .. And do that every few thousand feet on the way down to check progress ;)


Edit: oh and if you are in icing conditions or anticipate it, that changes things too
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Thanks...Does icing increase or decrease the distance?
 
Lucky Strike said:
3:1 doesn't work on the -9. To hold pressurization while descending aboving FL290, you can't go to flt idle. Only flt idle below FL290, and then it's 2:1.
I thought the same thing when checking out on it, but 3:1 really doesn't work...on -9.
Click to expand...

It worked when they were new..LOL
 
Used rule of 3's in the Lear. Amount of altitude to lose, drop the 0's, then multiplied by 3. 33000 to 11000, 22x3 = 66 miles from the fix at a 3000 fpm descent. Rinse and repeat a few times on the way down to verify combined with the TLAR method. Add in 7-10 miles if you have to slow to 250 at the end of the descent.

Would this work in the -9 as well? (thread got my curiosity)
 
OPECJet said:
Used rule of 3's in the Lear. Amount of altitude to lose, drop the 0's, then multiplied by 3. 33000 to 11000, 22x3 = 66 miles from the fix at a 3000 fpm descent. Rinse and repeat a few times on the way down to verify combined with the TLAR method. Add in 7-10 miles if you have to slow to 250 at the end of the descent.

Would this work in the -9 as well? (thread got my curiosity)
Click to expand...

It is the same formula as he showed me in his example. Alt need to lose*3 drop the zeros for a 3:1 and alt to lose*6 and drop the zeros for a 6:1. tailwind/icing/slowing down increase the distance, headwind decreases the distance.

Is that a fixed rate of descent or how does equate to feet/min?
 
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