Welcome to the NavList Message Boards.

NavList:

A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding

Compose Your Message

Message:αβγ
Message:abc
Add Images & Files
    Name or NavList Code:
    Email:
       
    Reply
    Re: Vulcan airborne sight reduction form?
    From: Antoine Couëtte
    Date: 2023 Aug 11, 05:13 -0700

    Just for fun, this quick computation rings a bell ..  about pre-cosmonaut training and pre-TPS exams.

    Under its best known - at least in France - "classical" form the centripetal acceleration "γ" is given as " γ = v**2 / r " with "v" being the [longitudinal] speed and "r" the instantaneous radius of turn.

    Through immediately jumping onto this classical form " γ = v**2 / r " formula, unfamilar candidates hassled into computing "r" from the starting data, to eventually discover that "r" did simply vanish in the final results.

    Too bad ... meanwhile the clock had been too fast running.

    A few Candidates - and the only ones able to complete all such exercises in a very limited time - were using the centripetal acceleration formula under this form " γ = v * ω " with "ω" being the angular motion.

    No need for any explicit "r" value, then ...

    In this example, with v = 540 kts = (540 * 1852 / 3600)  m/s = 277.8 m/s and ω = 1° / min = π /(180 * 60) rad/s = 291 E-6 rad/s, the lateral acceleration "γ" is instantly computed as : γ = 277.8 * 291 E-6 = 0.08081 m/s.

    Referring it to "g" as being the local gravity acceleration (at 9.81 m/s**2) yields :

    tan-1 (0.08081 / 9.81) = 28.3 '/° at 540 kts GS, or - as advertised -  57' of vertical offset for a 2° heading change per minute of time at 540 kts GS.

    Kermit

       
    Reply
    Browse Files

    Drop Files

    NavList

    What is NavList?

    NavList is a community devoted to the preservation and practice of celestial navigation and other methods of traditional position-finding. We're a group of navigators, navigation enthusiasts and hobbyists, mathematicians and physicists, and historians interested in all aspects of navigation but primarily those techniques which are non-electronic.

    To post a message, if you are already signed up as a NavList member, start a new discussion or reply to any posted message and use your posting code (this is a simple low-security password assigned when you join). You may also join by posting. Your first on-topic messsage automatically makes you a member, and a posting code will be assigned and emailed to you for future posts.

    Uniquely, the NavList message boards also permit full interaction entirely by email. You can optionally receive individual posts or daily digests by email, and any member can post messages by email (bypassing the web site) by sending to our posting address which is "NavList@NavList.net". This functionality is similar to a traditional Internet mailing list: post by email, read by email, reply by email. Most members will prefer the web interface here for posting and replying to messages.

    NavList is more than an online community... more about that another day.

    © Copyright notice: please note that the rights to all messages and posts in this discussion group are held by their respective authors. No messages or text or images extracted from messages may be reproduced without the explicit consent of the message author. Email me, Frank Reed, if you have any questions.

    Join / Get NavList ID Code

    Name:
    (please, no nicknames or handles)
    Email:
    Do you want to receive all group messages by email?
    Yes No

    A NavList ID Code guarantees your identity in NavList posts and allows faster posting of messages.

    Retrieve a NavList ID Code

    Enter the email address associated with your NavList messages. Your NavList code will be emailed to you immediately.
    Email:

    Email Settings

    NavList ID Code:

    Custom Index

    Subject:
    Author:
    Start date: (yyyymm dd)
    End date: (yyyymm dd)

    Visit this site
    Visit this site
    Visit this site
    Visit this site
    Visit this site
    Visit this site