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enter image description here

This in-flight photo provides a look into the pre-FMS era (also pre-INS), i.e., not having a programmable route.

How was the navigation managed back then? (Question limited to 2-crew jetliners, or jetliners that lacked a navigator position.)

What I'm interested in the division of crew duties, methodology of switching to stations (given the high ground speed of jet-liners), the expected/required accuracy, the use of reminders if any, etc. Basically, how it was managed.

I'm not asking how to navigate using VOR, NDB, etc., only the operational aspect.

Dissecting the photo above:

  1. Lack of FMS.
  2. Autopilot flying a heading select (heading 172, most probably not ATC issued) in cruise (PERF CRZ).
  3. Laid-back accuracy (not a bad thing).
    • For example, a VOR/LOC mode was available but wasn't used.
  4. NAV 1 radio selector.
  5. NAV 2 radio selector (opposite side).
  6. That's not an FMS, that's a PMS (Performance Management System) for flying the optimum vertical profile.
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  • $\begingroup$ Make sure you have your Pilot's Wizz Wheel, Gleim E-6B flight calculator and slide rule... $\endgroup$
    – CGCampbell
    Sep 3 at 15:32
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I've come across something interesting and very relevant to the operational aspect I've asked about.

Before FMCs became ubiquitous, pictorial routes were prepared for the crew to aid in navigation and navaid frequency/CRS changes as the flight progressed. They were not north-up, rather nose-up, and the nav log was printed bottom-up to match the nose-up orientation. Example from 1965:

enter image description here
— Ormonroyd, F. "Visual Aspects of Cockpit Management." The Aeronautical Journal 69.658 (1965): 651-659.

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Getting back to the early years:

  1. Plot route on a VFR and or IFR chart. The routing depends on Terrain vs Aircraft Performance, NOTAMS, Weather and winds aloft forecast etc.
  2. Create a fuel flight plan for this route that gives you all navigation information too, apart from the fuel requirement/progress calculation.
  3. Conduct a practical preflight briefing, The key to smooth navigation on these flights is preparedness and anticipation. Both pilots should be clear on peculiarities on the route and possible high workload situations that warrant special crew co-ordination.
  4. Position FIXES inflight in the absence of RNAV-like capabilities - for a 2 person crew, the FIX options are broadly, 'radio station passage', 'visual landmark', and 'dead-reckoning'. Flights are likely to start with radio aid guidance, probably a VOR radial that provides guidance to a distance of 100 to 250NM depending on the altitude. This initial Tracking gives a good idea of the actual winds aloft compared to the forecast and it can help, along with the Operational Flight Plan during the intervening dead-reckoning segment before the flight gets back to radio aid coverage or Radar vectors.
    To achieve the above:
  5. A few observation flights flights with an experienced crew at work is very instructive - better than the picture that is better than a thousand words.
  6. A dedicated classroom/one-on-one briefing by one of the experienced crew is a great confidence multiplier and it can dispel doubts and narrow down the focus during prep.
  • In case you need more specifics, please comment and we could embellish this answer appropriately.
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