Drive link

February 15, 2010 by Tim McAdams

Connecting the rotating swash plate to the rotor shaft is an assembly known as the drive link. Because the swash plate needs to move up and down and pivot, the drive link has a joint that acts like a scissor – as such it is sometimes referred to as a scissors link. I have had several students ask me why it is needed.

The swash plate has a rotating and non-rotating side. The non-rotating side is on the bottom and is connected to the flight controls. The rotating side is on the top and is connected via pitch links to each rotor blade. The collective control moves the entire swash plate assembly up and down to change the pitch on each blade equally. The cyclic control tilts the swash plate, changing each blade’s pitch independently depending on its position around the rotor disk. This tilts the rotor disk in the desired direction.

Since the rotor mast runs from the transmission up through a sleeve that the swash plate moves around, there needs to be a method of turning the rotating part of the swash plate. This is the function of the drive link as it connects the mast directly to the swash plate. It is critical that this part be functioning correctly.

During preflight it should be examined closely as the failure of the drive link has caused several accidents. On the Bell 222 an improperly sized bolt that attached the drive link to the swash plate allowed play which caused the bolt to fail. As you can imagine without the drive link the blades will continue turning the swash plate through the pitch links. This stresses the pitch links in a manner they were not designed to handle and can result in a pitch link failure. In this case with the Bell 222 it caused an in-flight break up.

In 1988 the pilot of a Bell 47 spraying a field reported an extreme vibration followed by a loss of control and hard landing. Then in 1992 a CFI and student flying another Bell 47 also felt a sudden and severe vibration and managed to successfully autorotoate to a field. In both cases the center bolt connecting the drive link was missing and disconnected drive to the swash plate.

Tags:

21 Responses to “Drive link”

  1. Brendan Fitzpatrick Says:

    Good stuff, Tim! Keep it up – off to Heli-Expo in Houston on Sunday.

  2. Michael Muma Says:

    Good info…A picture of the failed parts would be informative in this case – especially the one where an inappropriate bolt was used, and the ones where the autorotation was successful showing the damaged parts after the fact.

  3. Ehud Gavron Says:

    There’s an email version of this blog? I’d love to get notified of changes. Right now I just have a script check it ;)

    Ehud

  4. decides deciding decidua decidual deciduous deciduously deciduousness decigram decigrams decile deciliter deciliters decimal decimalization decimalize decimalized decimalizes decimalizing decimally decimals decimate decimated decimates decimating decimati Says:

    Excellent confident synthetic attention pertaining to fine detail and can foresee problems just before these people happen.

    Also visit my homepage; decides
    deciding
    decidua
    decidual
    deciduous
    deciduously
    deciduousness
    decigram
    decigrams
    decile
    deciliter
    deciliters
    decimal
    decimalization
    decimalize
    decimalized
    decimalizes
    decimalizing
    decimally
    decimals
    decimate
    decimated
    decimates
    decimating
    decimation
    decimeter
    decimeters
    decipher
    decipherable
    deciphered
    deciphering
    deciphers
    decision
    decisional
    decisions
    decisive
    decisively
    decisiveness
    decistere
    decisteres
    deck
    decked
    decker
    deckers
    deckhand
    deckhands
    decking
    deckings
    deckle
    deckles
    decks
    declaim
    declaimed
    declaimer
    declaimers
    declaiming
    declaims
    declamation
    declamations
    declamatory
    declarable
    declarant
    declaration
    declarations
    declarative
    declaratively
    declarator
    declaratory
    declare
    declared
    declarer
    declarers
    declares
    declaring
    declasse
    declassification
    declassifications
    declassified
    declassifies
    declassify
    declassifying
    declassing
    declension
    declensions
    declinable
    declination
    declinational
    declinations
    declinatory
    declinature
    decline
    declined
    decliner
    decliners
    declines
    declining
    declivities
    declivity
    deco
    decoct
    decocted
    decocting
    decoction
    decocts
    decode
    decoded
    decoder
    decoders
    decodes
    decoding
    decodings
    decollated
    decollete
    decolonization
    decolonize
    decolonized
    decolonizes
    decolonizing
    decommission
    decommissioned
    decommissioning
    decommissions
    decompensate
    decompensated
    decompensates
    decompensating
    decompensation
    decompensations
    decomposability
    decomposable
    decompose
    decomposed
    decomposer
    decomposers
    decomposes
    decomposing
    decomposition
    decompositions
    decompress
    decompressed
    decompresses
    decompressing
    decompression
    decompressions
    decompressive
    decongest
    decongestant
    decongestants
    decongested
    decongesting
    decongestion
    decongestive
    decongests
    decontaminate
    decontaminated
    decontaminates
    decontaminating
    decontamination
    decontaminations
    decontaminator
    decontaminators
    decontrol
    decontrolled
    decontrolling
    decontrols
    decor
    decorate
    decorated
    decorates
    decorating
    decoration
    decorations
    decorative
    decoratively
    decorativeness
    decorator
    decorators
    decorous
    decorously
    decorousness
    decors
    decorticate
    decorum
    decorums
    decoupage
    decouple
    decoy
    decoyed
    decoyer
    decoyers
    decoying
    decoys
    decrease
    decreased
    decreases
    decreasing
    decreasingly
    decree
    decreed
    decreeing
    decreer
    decreers
    decrees
    decrement
    decrements
    decrepit
    decrepitly
    decrepitude
    decrescendo
    decrescendos
    decrial
    decrials
    decried
    decrier
    decriers
    decries
    decriminalization
    decriminalize
    decriminalized
    decriminalizes
    decriminalizing
    decrowns
    decry
    decrying
    decrypt
    decrypted
    decrypting
    decryption
    decryptions
    decrypts
    dedicate
    dedicated
    dedicatee
    dedicates
    dedicating
    dedication
    dedicational
    dedications
    dedicator
    dedicators
    dedicatory
    deduce
    deduced
    deduces
    deducible
    deducing
    deduct
    deducted
    deductibility
    deductible
    deductibles
    deducting
    deduction
    deductions
    deductive
    deductively
    deducts
    deed
    deedbox
    deeded
    deedier
    deeding
    deedless
    deeds
    deedy
    deejay
    deejays
    deem
    deemed
    deeming
    deemphasis
    deemphasize
    deemphasized
    deemphasizes
    deemphasizing
    deems
    deep
    deepen
    deepened
    deepener
    deepeners
    deepening
    deepens
    deeper
    deepest
    deeply
    deepness
    deeps
    deer
    deerfly
    deerflys
    deers
    deerskin
    deerskins
    deerstalker
    deerstalkers
    deerweed
    deerweeds
    deeryard
    dees
    deescalate
    deescalated
    deescalates
    deescalating
    deescalation
    deescalations
    deface
    defaced
    defacement
    defacements
    defacer
    defacers
    defaces
    defacing
    defacto
    defalcate
    defalcated
    defalcates
    defalcating
    defalcation
    defalcations
    defamation
    defamations
    defamatory
    defame
    defamed
    defamer
    defamers
    defames
    defaming
    defamingly
    defat
    defats
    defatted
    default
    defaulted
    defaulter
    defaulters
    defaulting
    defaults
    defeat
    defeated
    defeater
    defeaters
    defeating
    defeatism
    defeatist
    defeatists
    defeats
    defecate
    defecated
    defecates
    defecating
    defecation
    defect
    defected
    defecter
    defecters
    defecting
    defection
    defections
    defective
    defectively
    defectiveness
    defector
    defectors
    defects
    defeminize
    defeminized
    defeminizing
    defence
    defences
    defend
    defendable
    defendant
    defendants
    defended
    defender
    defenders
    defending
    defends
    defense
    defensed
    defenseless
    defenselessly
    defenselessness
    defenses
    defensibility
    defensible
    defensibly
    defensing
    defensive
    defensively
    defensiveness
    defer
    deference
    deferent
    deferential
    deferentially
    deferment
    deferments
    deferrable
    deferral
    deferrals
    deferred
    deferrer
    deferrers
    deferring
    defers
    defiance
    defiances
    defiant
    defiantly
    defibrillate
    deficiencies
    deficiency
    deficient
    deficiently
    deficit
    deficits
    defied
    defier
    defiers
    defies
    defile
    defiled
    defilement
    defilements
    defiler
    defilers
    defiles
    defiling
    defilingly
    definable
    definably
    define
    defined
    definement
    definer
    definers
    defines
    defining
    definite
    definitely
    definiteness
    definition
    definitions
    definitive
    definitively
    definitiveness
    deflagrate
    deflagrated
    deflagrates
    deflagrating
    deflagration
    deflagrations
    deflate
    deflated
    deflates
    deflating
    deflation
    deflationary
    deflations
    deflator
    deflators
    deflea
    deflect
    deflectable
    deflected
    deflecting
    deflection
    deflections
    deflective
    deflector
    deflectors
    deflects
    defloration
    deflorations
    deflorescence
    deflower
    deflowered
    deflowering
    deflowers
    defoam
    defoamed
    defoamer
    defog
    defogged
    defogger
    defoggers
    defogging
    defogs
    defoliant
    defoliants
    defoliate
    defoliated
    defoliates
    defoliating
    defoliation
    defoliations
    defoliator
    defoliators
    deforest
    deforestation
    deforested
    deforesting
    deforests
    deform
    deformable
    deformation
    deformations
    deformative
    deformed
    deformer
    deformers
    deforming
    deformities
    deformity
    deforms
    defraud
    defraudation
    defrauded
    defrauder
    defrauders
    defrauding
    defrauds
    defray
    defrayable
    defrayal
    defrayals
    defrayed
    defrayer
    defrayers
    defraying
    defrayment
    defrays
    defrock
    defrocked
    defrocking
    defrocks
    defrost
    defrosted
    defroster
    defrosters
    defrosting
    defrosts
    deft
    defter
    deftest
    deftly
    deftness
    defunct
    defunctive
    defunctness
    defuse
    defused
    defuses
    defusing
    defuze
    defuzed
    defuzes
    defuzing
    defy
    defying
    degas
    degass
    degassed
    degasses
    degassing
    degauss
    degaussed
    degausses
    degaussing
    degeneracies
    degeneracy
    degenerate
    degenerated
    degenerately
    degenerateness
    degenerates
    degenerating
    degeneration
    degenerations
    degenerative
    degerm
    degermed
    degradable
    degradation
    degradations
    degrade
    degraded
    degradedly
    degradedness
    degrader
    degraders
    degrades
    degrading
    degrease
    degreased
    degreases
    degreasing
    degree
    degreed
    degrees
    degum
    degummed
    degumming
    degums
    dehorn
    dehorned
    dehorner
    dehorning
    dehorns
    dehumanization
    dehumanize
    dehumanized
    dehumanizes
    dehumanizing
    dehumidification
    dehumidified
    dehumidifier
    dehumidifiers
    dehumidifies
    dehumidify
    dehumidifying
    dehydrate
    dehydrated
    dehydrates
    dehydrating
    dehydration
    dehydrator
    dehydrators
    dehydrogenate
    dehydrogenated
    dehydrogenates
    dehydrogenating
    dehydrogenation
    dehypnotize
    dehypnotized
    dehypnotizing
    dei
    deice
    deiced
    deicer
    deicers
    deices
    deicidal
    deicide
    deicides
    deicing
    deific
    deifical
    deification
    deifications
    deified
    deifier
    deifiers
    deifies
    deiform
    deify
    deifying
    deign
    deigned
    deigning
    deigns
    deionization
    deionizations
    deionize
    deionized
    deionizes
    deionizing
    deism
    deisms
    deist
    deistic
    deists
    deities
    deity
    deja
    deject
    dejected
    dejectedly
    dejectedness
    dejecting
    dejection
    dejections
    dejects
    dekagram
    dekagrams
    dekaliter
    dekaliters
    dekameter
    dekameters
    dekares
    del
    delaware
    delawarean
    delay
    delayed
    delayer
    delayers
    delaying
    delays
    dele
    delead
    delectable
    delectably
    delectation
    delectations
    deled
    delegacies
    delegacy
    delegalizing
    delegant
    delegate
    delegated
    delegatee
    delegates
    delegati
    delegating
    delegation
    delegations
    delegatory
    deleing
    deles
    delete
    deleted
    deleterious
    deleteriously
    deleteriousness
    deletes
    deleting
    deletion
    deletions
    delft
    delfts
    delhi
    deli
    deliberate
    deliberated
    deliberately
    deliberateness
    deliberates
    deliberating
    deliberation
    deliberations
    deliberative
    deliberatively
    deliberator
    delicacies
    delicacy
    delicate
    delicately
    delicateness
    delicates
    delicatessen
    delicatessens
    delicious
    deliciously
    deliciousness
    delict
    delicti
    delicto
    delight
    delighted
    delightedly
    delightful
    delightfully
    delightfulness
    delighting
    delights
    delime
    deliming
    delimit
    delimitating
    delimitation
    delimitations
    delimitative
    delimited
    delimiter
    delimiters
    delimiting
    delimits
    delineate
    delineated
    delineates
    delineating
    delineation
    delineations
    delineative
    delinquencies
    delinquency
    delinquent
    delinquently
    delinquents
    deliquesce
    deliquesced
    deliquescence
    deliquescent
    deliquesces
    deliquescing
    deliria
    deliriant
    delirifacient
    delirious
    deliriously
    deliriousness
    delirium
    deliriums
    delis
    delist
    deliver
    deliverable
    deliverables
    deliverance
    delivered
    deliverer
    deliverers
    deliveries
    delivering
    delivers
    delivery
    dell
    dells
    delly
    delouse
    deloused
    delouses
    delousing
    delphinia
    delphinium
    delphiniums
    delta
    deltaic
    deltas
    deltic
    deltoid
    deltoids
    delude
    deluded
    deluder
    deluders
    deludes
    deluding
    deludingly
    deluge
    deluged
    deluges
    deluging
    delusion
    delusional
    delusionary
    delusionist
    delusions
    delusive
    delusively
    delusiveness
    delusory
    deluxe
    delve
    delved
    delver
    delvers
    delves
    delving
    demagnetization
    demagnetize
    demagnetized
    demagnetizes
    demagnetizing
    demagnification
    demagog
    demagogic
    demagogies
    demagogs
    demagogue
    demagoguery
    demagogues
    demagogy
    demand
    demandable
    demanded
    demander
    demanders
    demanding
    demandingly
    demands
    demarcate
    demarcated
    demarcates
    demarcating
    demarcation
    demarcations
    demarcator
    demarcators
    demarche
    demarches
    demarking
    demasculinize
    demasculinized
    demasculinizing
    demean
    demeaned
    demeaning
    demeanor
    demeanors
    demeans
    dement
    demented
    dementedly
    dementia
    dementias
    dementing
    dements
    demerit
    demerited
    demeriting
    demerits
    demesne
    demesnes
    demeter
    demigod
    demigods
    demijohn
    demijohns
    demilitarization
    demilitarize
    demilitarized
    demilitarizes
    demilitarizing
    demimondain
    demimondaine
    demimondaines
    demimonde
    demineralization
    demineralize
    demineralized
    demineralizes
    demineralizing
    demise
    demised
    demises
    demising
    demit
    demitasse
    demitasses
    demits
    demitted
    demiurge
    demiurges
    demo
    demob
    demobbed
    demobbing
    demobilization
    demobilizations
    demobilize
    demobilized
    demobilizes
    demobilizing
    demobs
    democracies
    democracy
    democrat
    democratic
    democratical
    democratically
    democratism
    democratization
    democratize
    democratized
    democratizes
    democratizing
    democrats
    demode
    demodulate
    demodulated
    demodulates
    demodulating
    demodulation
    demodulations
    demographer
    demographers
    demographic
    demographically
    demographics
    demographies
    demography
    demoiselle
    demoiselles
    demolish
    demolished
    demolisher
    demolishes
    demolishing
    demolition
    demolitionist
    demolitions
    demon
    demoness

  5. magic article submitter download Says:

    Very nice post. I just stumbled upon your blog aand wanted to say that I have truly enjoyed surfing around your blog posts.
    In any case I will be subscribinng to your feed and I hope you
    write again very soon!

    My blog: magic article submitter download

  6. fb ads cracked price Says:

    Generally I don’t learn article on blogs, however I wish to
    say that this write-up very compelled me to take a look at
    and do so! Your writing taste has been surprised me. Thanks, quite
    nice article.

    Also visit my web blog fb ads cracked price

  7. hangoutdoctrine.blogspot.com Says:

    Hello to all, the contents present at this web page are actually remarkable for
    people knowledge, well, keep up the nice work fellows.

    Also visit my website – Ryan Mckinney hangout- does it work?, hangoutdoctrine.blogspot.com,

  8. Hangout Marketing Says:

    Good way of telling, and fastidious article to take data on the topic of
    my presentation subject, which i am going to deliver in school.

    Here is my blog post; Hangout Marketing

  9. kona coffee Says:

    Hey there! I understand this is kind of off-topic however I had to ask.

    Does operating a well-established website like yours take a large amount
    of work? I am completely new to writing a blog but I do write
    in my diary on a daily basis. I’d like to start a blog
    so I can easily share my personal experience and feelings online.
    Please let me know if you have any ideas or tips for new aspiring bloggers.
    Thankyou!

  10. Lorenzo Sirpilla Says:

    Hello, i think that i saw you visited my weblog thus i came to “return the favor”.I am trying to find things to enhance my website!I
    suppose its ok to use a few of your ideas!!

  11. rea Says:

    Hey There. I found your blog using msn. This is a really well written article.

    I will be sure to bookmark it and come back too read more of your useful info.
    Thanks for the post. I will definitely return.

    my web-site – rea

  12. amazing cheap fake oakley sunglasses wholesalers Says:

    When you uncover which kind of entire body you have, it would be more simple to stay in superior actual physical shape. It is possible to glimpse soon after you. Based mostly over the scientists, the existence of different physical structure just reveals that we are all one of a kind. Genetics also plays a part inside our setting up exercise routines. Reports have verified us that beforehand all those hormones in addition to the line is exclusive both equally in human and animal types, like our conduct and performance.

  13. fake michael kors bags Says:

    Yesterday evening, I got to hang having Rachael Jimmy throughout Chicago, in the party that will observe their table range.
    fake michael kors bags
    [url=http://www.redseamax.com/support_mk.html]fake michael kors bags[/url]

  14. ゲーム機本体 Says:

    Collection of helpful options to discover more regarding women before you are left behind.
    ゲーム機本体

  15. kayaks for sale Says:

    Excellent, what a webpage it is! This weblog provides valuable information to us, keep it up.

    my website: kayaks for sale

  16. レイバン サングラス Says:

    The Best Solutions To Gain knowledge watch Plus The Way One Could Connect with The watch Elite

  17. replica ray ban sunglasses Says:

    I had the cabability to see a few of the holiday getaway plates she’s going out and about, and also individual, will they be lovely
    replica ray ban sunglasses

  18. babyliss pro perfect curl Says:

    I managed to get a chance to view many of the holiday dinners she is in business up, and then fella, are they really cute
    babyliss pro perfect curl

  19. ray ban sunglasses Says:

    I bought enable you to witness a lot of the getaway dishes this woman is started outside, and individual, is he or she cute
    ray ban sunglasses

  20. ケイトスペード(Kate Spade) バッグ Says:

    japan aids all of us by including plenty of special features and options. It’s a unvaluable thing for every fan of japan.

  21. Shelby Says:

    Une fois de plus un poste assurément instructif

Leave a Reply

*