USAF and RAAF 707 aircraft, what is the navagation system that is used?

Not sure, but I think they use an FMC

Not sure what your time period is but for USAF from 1970 to 1975 on a KC-135 the only navigation aids were DR, Loran A, Celestial, pressure and radar (over land).

As Trailboss says, in the 70's there were not many choices when it came to nav stuff. Doppler was the big hitter in the 60' & 70's. If they are flying around today there are many types of nav systems available. IRS is a big leader with GPS backup and of course some computer to keep it all neat.

Lou

Is IRS similar to INS as far as inner-workings go? By that I mean, do they operate on similar principles?

Yes pretty much. INS (inertial nav system) older type stuff.

IRS (inertial reference system) uses laser ring gyros and is a newer system.

INS - 747 -100 & maybe 200
IRS - 757, 767, and up.

The end product is the same.

Lou,
According to the CS 707-300, the plane was equiped with both doppler and INS. In what instant would you use one system in place of the other.
BTW, thanks so much for taking all my question. I'm not a real pilot like a lot of people here are so I don't have a lot of resources for obtaining this type of information.

An INS system could have been retrofitted later, but from what I have read, early INS was used in missiles more than aircraft, and a 707 from the late fifties would probably not have had INS originally.

Thanks everyone, for your input on the subject.

To summarize from the information input given, the 707 aircraft
navagation system can be up graded, to virtually any navagation system available?

As I understand the USAF and RAAF still operate the 707 aircraft at the present time?

BrianG,

The 707 of the Captain Sim era could have had an INS added, but none of the 707 I flew through the early 80's had INS. It's one thing to have just one plane and add all the fancy stuff, but the airlines fly under FAA Part 121 and the cost of refitting a fleet of planes with expensive stuff like INS and going through the re-certification process would be pretty high. That's not to say it was not done, but the 707 was fast being replaced by newer planes that burned less fuel and carried more people. We had a few 727's that had GPS and a basic performance computer installed, but it was limited to just a few planes.

Lou

Lou

It's great to read your answers and learn from your knowledge base, as a professional pilot.

John

Lou,
Thanks for all your input and taking my questions. It's really fun learning all this and enhances my flight sim experiences. So which 707 variations did TWA use and which ones did you have the pleasure of flying? Are the difference between the variations clear or are they hard to notice.?

TWA had 707-131 ( the 31 part was the number assigned to TWA by Boeing .) This plane was a non fan engine with water injection.
Then there was the 707-331 - a larger 707 non fan plane.
Next was the 707-131B - a true rocket ship. Small 707 with fan engines. A real trip to fly!  :-*
And then the last of the group was the 707-331B series. This included the 707-331BA, BAH and C versions. All had the larger fan engine with various leading edge flap differences and higher take off & landing weights. The BA & BAH were similar, but the H stood for heavy - it had stronger landing gear.

A side note, the 727-200 was just a few inches longer than the 707-131B. There were always the pilots that said they flew the "big" Boeing - meaning the 707, but when the 727-200 came along they had to shut-up!  ;D  Of course the 747 ended all that BS.  :P

Lou

Great stuff Lou. It would seem that the 707-131 was not a big money maker for airlines being it held less passengers that the 300 series.Was the 707-131 used on shorter routes ? It seems in general the key to making a 707 profitable would be to keep it in the air on longer flights being it used so much fuel getting to cruising altitude. But with fuel at 15 cents/gallon back then maybe that really wasn't a consideration?
And what did water injection on the engines accomplish? Was that for addition power on take off? I just remember water injected engines created much dark smoke on take off.

BrianG asked: It would seem that the 707-131 was not a big money maker for airlines being it held less passengers that the 300 series.Was the 707-131 used on shorter routes ? It seems in general the key to making a 707 profitable would be to keep it in the air on longer flights being it used so much fuel getting to cruising altitude. But with fuel at 15 cents/gallon back then maybe that really wasn't a consideration?
And what did water injection on the engines accomplish? Was that for addition power on take off? I just remember water injected engines created much dark smoke on take off.

The 707-100 series was a bit smaller, but the seating config was even more important to the passenger numbers. We had some 707-300's that were all first class and some that were all coach and the latter was not a nice product, but was necessary to be able to make money with charter fares. Either version was able to go coast-to-coast, but only the -300's went over the pond.

The 707-131 "water wagon" was a filthy plane on takeoff. It would carry 5,500 gallons of special water that was injected into the aft section of the engine. What it was intended to do was increase thrust by adding to the mass of the exhaust. It did do that somewhat, but what it did mostly was soot up the sky with copious black smoke and make a hell of a lot of noise. You had to use all the water since any left over would freeze in the tank and cause problems. Most pilots hated to use the water and some dumped it on the taxiway before take off.  :o

I remember taking off out of Shannon on a charter at max gross with a 707-331 and using every foot of the runway.  :-X This was an underpowered plane if there ever was one. The 707-131B on the other hand was a hoot to fly - Hang On here we goooooooo...  :D

Lou

Hey Lou, Yes- even my CS 707-300 barely lifts off 16L at KSEA fully loaded and has a heck of a time getting to cruising altitude. Many times, if loaded to max TOW I have to level off every now and then to pick up some airspeed before I continue the ascend. Was it like that in the real world with a fully loaded 707-331?
Also,was water injection mandatory for a successful take off on the 100's or was it just used when the plane was heavily loaded? The 100 sounds like a really fun plane to fly based on what you've been talking about.
I would imagine a real stick and rudder man like yourself would be bored with" fly by the wire" planes these days?
Did 707 pilots ever use dead reckoning as a test for electronic navigation or vice-verse? I do that when sailing just for the sake of amusement. I would imagine dead reckoning would be tricky moving at 500k. I have seen youtube videos of Pan Am 707 pilots actually using a sextant. My have times have changed.