alpinewarren 1 Posted November 23 I was lucky enough to have some time in the DC-8 and well and DC-9 and other early turbojets - Being that very set airspeeds are needed for efficient climb to higher flight levels I would love to see an implemented IAS hold mode with a speed bug... It was the only way we climbed - VS hold requires a lot of baby-sitting. Well done on this product! 1 Share this post Link to post
Mathijs Kok 32079 Posted November 24 I believe those were optional were they not? Share this post Link to post
thibodb 2 Posted November 24 7 hours ago, Mathijs Kok said: I believe those were optional were they not? Per the Operating manual pg 24 Pitch Selector Switch The switch will not hold in MACH HOLD or IAS HOLD since these functions are not usable as autopilot modes of operation. I would agree with Alpine that IAS is by far the preferred way to climb any aircraft not just turbojet. This function is doable though. Leonardo's Maddog has this function inbuilt into their automation. Share this post Link to post
alpinewarren 1 Posted November 25 On 11/24/2019 at 7:55 AM, Mathijs Kok said: I believe those were optional were they not? Perhaps optional but I never flew one that didn't have it - And you could bust a checkride climbing with the VS hold. Once above @FL220 heavy you could get in deep behind the L/D curve if not careful and very attentive and have no other option that to descend to get your speed back up. :) Share this post Link to post
Mace_RB 37 Posted November 30 On 11/25/2019 at 11:32 AM, alpinewarren said: Perhaps optional but I never flew one that didn't have it - And you could bust a checkride climbing with the VS hold. Once above @FL220 heavy you could get in deep behind the L/D curve if not careful and very attentive and have no other option that to descend to get your speed back up. I may be mistaken, but I think he has modelled a 1960's-era DC-8, which did not have IAS hold. Share this post Link to post
AAC47 14 Posted Monday at 09:26 PM We seldom used IAS HOLD on DC-8 62-63 or DC-9 in SAS as it was too erratic....... For climb OAT changes made too much impact of the Climb Rate so it was better to closely monitor climb with V/S input and adjust when needed For Optimal Descent Planning V/S rate better matched Distance and Altitude to Destination If You want a specific climb/descent rate according to restriction/performance the Stoneage A/P must be used in V/S mode or why not manual flying....:)) This is my very personal opinion regarding how to fly DC-8 and DC-9.................... Share this post Link to post
Michael2 222 Posted Monday at 11:48 PM The manuals were very specific for the 50 series in stating that IAS hold was not implemented. The text from the real life manual in this respect is copied into the one that ships with the product. Share this post Link to post