HSI vs. CDI

Discussion in 'Cleared for the Approach' started by MBDiagMan, Jul 12, 2019.

  1. MBDiagMan

    MBDiagMan En-Route

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    I have flown a CDI for many years and feel quite comfortable reading and using one. The only exposure I have ever had to an HSI is on the private and instrument written tests and it didn’t seem very intuitive to me. Maybe flying one would be easier than figuring out the FAA’s questions about them.

    I have a chance to buy a high end autopilot setup that includes an HSI. I suppose that with a GPS slaved autopilot, maybe it doesn’t matter because you’re not normally hand flying it anyway, but I think I should be proficient with whatever is in the panel.

    So.... is the HSI intuitive to migrate to after being comfortable only with a CDI?
     
  2. jordane93

    jordane93 Final Approach

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  3. mondtster

    mondtster En-Route

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    Think of it as two instruments combined into one. I’d take an HSI over a CDI any day, if I had the choice.

    I think they’re easy to adapt to. I haven’t run into any students that struggled with switching to an HSI, with a little coaching.
     
  4. RussR

    RussR Cleared for Takeoff

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    In my experience both with myself and with teaching others, an HSI is one of those things that can be really difficult to wrap your head around when you're seeing it on paper, like for the test. But once in the airplane, it's totally intuitive and takes very little time to get used to. Highly preferred over a CDI.
     
  5. luvflyin

    luvflyin Final Approach

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    Yup to all the above. The learning curve is very steep. You'll have it down in an hour if not minutes
     
  6. EdFred

    EdFred Touchdown! Greaser! PoA Supporter

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    +1 for the HSI
     
  7. PaulS

    PaulS Final Approach

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    HSI baby, it's all right there.
     
  8. 455 Bravo Uniform

    455 Bravo Uniform En-Route PoA Supporter

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    And when I’m not using my HSI for nav or autopilot, I’ve gotten into the habit of setting the course to runway heading and setting the heading bug to wind direction. Helps me visualize crosswind, confirms I’m landing into the wind, and helps with proper runway ID, as well as downwind and base turns for my highwing plane. I do it before takeoff too. Just something stupidly simple I got into when I first bought the plane before I started using A/P and nav functions.
     
    flyingcheesehead and Michael A like this.
  9. MBDiagMan

    MBDiagMan En-Route

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    Thanks guys. I didn’t see even one fence sitter. It was unanimous. I will cross the HSI concern off the list of possible objections. Now all I have to do is decid3 if I want to spend 5he money.
     
  10. MBDiagMan

    MBDiagMan En-Route

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    Well shucks! The autpilot turned out to be 28V, non dual voltage so I can’t use it. Sometimes decisions are out of your control.
     
  11. Jim_CAK

    Jim_CAK Pre-takeoff checklist PoA Supporter

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    ADB527C6-6ABA-4A42-9A4A-5491DBE51C7A.jpeg
    Any chance of getting an transformer to step up the voltage to from 12V to 28V? Our very early model G430 was 28 volt only and Garmin had a 3rd party transformer to adapt to 12 volt airplanes. Maybe you could contact them to see if it would work for your application.
     
  12. bobmrg

    bobmrg En-Route

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    A transformer for DC? Transformers are for AC applications.

    Bob
     
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  13. Jim_CAK

    Jim_CAK Pre-takeoff checklist PoA Supporter

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    Ok - for us laymen, how about a regulated power booster?
     
  14. asicer

    asicer En-Route

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    In the stone ages, it was much easier to step down DC voltage than step up. Nowadays in the real world it's not that big a deal. However, the aviation world is still stuck in the stone ages, so I don't know.
     
  15. Clip4

    Clip4 En-Route

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    http://www.luizmonteiro.com/Learning_HSI_Sim.aspx
     
  16. chartbundle

    chartbundle Cleared for Takeoff

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  17. olasek

    olasek Pattern Altitude

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    I flew with 'frustrating' CDI and when I discovered there was a thing called HSI which I thought it was an absolutely miraculous piece of hardware.
    All the problems I had with CDI instantly disappeared.
     
    Last edited: Jul 16, 2019
  18. aterpster

    aterpster Pattern Altitude

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  19. Clip4

    Clip4 En-Route

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    midlifeflyer likes this.
  20. Unit74

    Unit74 Ejection Handle Pulled

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    Shut up Marty.... just go with it.
     
  21. N1120A

    N1120A Line Up and Wait

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    HSIs are so much nicer.
     
  22. Firepac

    Firepac Pre-Flight

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    In a glass cockpit the CDI is part of the HSI no?
     
  23. N1120A

    N1120A Line Up and Wait

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    An HSI replaces a CDI and combines the functions of a CDI and heading indicator.
     
  24. flyingron

    flyingron Touchdown! Greaser!

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    And the omnibearing selector.
     
  25. Ryan F.

    Ryan F. Line Up and Wait

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    RussR said it best - highly preferred!
     
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