the learning never stops!

GVII User's Group


All of us are smarter than one of us. That is the theme here. My intention is to collect, validate and distribute GVII intel through a group of GVII users willing to share. Additionally, I will collect questions and try to get them answered from known experts. Of course sometimes the experts don't know, if that is the case I'll open it up to the group.


If you would like to join this group the only qualification needed is the keys to a GVII, or the prospect of a GVII in the future, and the desire to learn and help others to learn. Just use the contact button on the bottom or top of this page and send me an email.

Organization of These Notes

Whenever I post a number of notes I'll email everyone using a "blind copy" so you will only see your own email address and mine. I'll include the notes in the email. You can reference past notes here. I'll try to incorporate those notes where they belong in the website but also here, below. The most recent will be on top.

But just because I have this incessant need to group things alphabetically, chronologically, or topically, here is an alphabetic list to get you started. (Scroll below the list of the most recents.)

Most Recent Notes (on top)

Entry into Service Lessons Learned

Has your entry into service been trouble free? What do you wish you knew before you had to learn it the hard way? Here are a few submissions.

Post by: Various

Posted: 25 September 2019

  1. Some airports have a 75,000 lb. maximum weight restriction that other Gulfstreams are able to get around using an ASC that "officially" reduces our maximum ramp weight. Gulfstream says this is in the works for the G500.
  2. The HF defaults to Emergency mode and wrong settings. It is fairly easy to correct but sometimes it doesn’t take the changes until a few tries.
  3. The GCMS has been acting up now and then freezing the moving map on cabin monitors. Gulfstream Maintenance techs are now telling us to wait until the IRUs Align before turning on Cabin power. A 650 driver confirms this is their SOP. This means you will be using flashlights for a few minutes. You cannot reset the cabin using a SSPC, it can only be reset by going to black.
  4. We have also heard of fueling faults resulting from fueling before the IRUs have finished aligning.
  5. The break away trim around the aft lav door...well it sure does break away. It’s often busted for us, scotch tape (shhhh!) to the rescue. When the aft bag door is open and the MED is open a differential pressure causes it to slam and bust. Very flimsy.
  6. Don’t put anything on the floor during power up in the forward lav as there’s a weight sensor. This was a favorite spot for me and others to put a backpack or briefcase. What happens is if the system senses weight there during a system power up it disables water to the forward lav and you’re out of luck until depowering. Very little info out there, as in none, on this and we lost a lot of time chasing this down.
  7. Gulfstream Maintenance told me the 3 (now 4) minute wing heat limitation is basically gumming up deice fluid and causing a lot of bright work issues. He was involved in a deice departure last winter that the bright work needed to buffed out twice to make leading edges look good.
  8. We had the acoustic door closed while waiting on PAX. Once they arrived, we opened the door, but it was how it was opened that affected the CAS. I know we are all trying to be gentle with the hinges and latches and rightfully so. In this case, the door was not retracted past the plastic lever/locking mechanism that makes the acoustic door CAS appear for takeoff and landing. It's the same lever on top of the door that we actuate to move the door open from the stowed position. We had briefed aborting only for conditions unsafe for flight, thus continued the takeoff. Point of the story, we can still be gentle with everything but make sure that door in particular moves past the locking mechanism. Here are two photos. The one on the right “not latched” was closed just enough to not generate the CAS on taxi. However, during acceleration for takeoff, it moved aft enough to open the switch and generate the CAS.

  9. images

    Photo: Accoustic door fully open (left), not fully open (right)

    Click photo for a larger image

  10. Maintenance has asked us to spread the word on the cockpit floor compartment hinges. The current hinges are weak, so please open and close them gently. They believe they are breaking when the doors are overextended while opening.
  11. Maintenance opens the lav door and sets the door stopper when the aircraft arrives back home. If the stopper is set "lever under the deadbolt," the door is more difficult to move. However, with much force, it rips the stopper off the bottom of the door.
  12. Auto switch of speeds to 250 below 10,000 is dependent solely on the rate of descent and when the FCS determines the speed needs to start slowing in order to meet the limitation. This is regardless of altitude Pre-Selector or whether VNAV or FLCH/VSPD is being used. If you look at the VSD, you can see a notch where the descent path shallows out a bit, this corresponds to the altitude at which the FCS has calculated the slow down.

Type I De-ice / Anti-Ice

Section 01-30-50 of the AFM says the only kind of deicing fluid you can use is Type 1, period. Why is that?

Post by: ja1

Posted: 24 September 2019

I've heard two stories out there about the reason Type 4 is not yet approved: Gulfstream hasn't tested the engines for it yet or the fluid cakes on the wings because of the requirement to preheat them 4 minutes prior to takeoff. Turns out the reason does have to do with testing, but not with the engines. This from someone in the G500/G600 Program:

The FAA has asked Gulfstream to test all fluid types per the 2015 policy memo PS-ANM-25-10 even though this was not part of the originally agreed cert basis of the G500 & G600 models. This new requirement was levied on the aircraft prior to G500 AFM revision 3 and the basic version of the G600 AFM. The limitation will be lifted pending successful completion of the testing as described in the policy statement. Target for this task completion is December of 2019. I believe when you review the policy memo you will find it does not mention anything specifically about engine testing. Indeed, fluid susceptibly of the engine is demonstrated and certified during the separate Part 33 engine test program."

G500 AOM Rev 4

The highlights for revision mention contaminated runway takeoff and landng performance plus a few broken links. The only really significant change is we now have a way of adjusting landing distances on contaminated runways for the type of contaminant, the temperature, and our chosen speed additive.

Post by: ja1

Posted: 23 September 2019

AOM, §05-09-10, Crosswind Limitations on Contaminated Runways — No significant change, they simply fixed two placeholders that said "cross reference" instead of the actual link that got by the editors for Revision 3.

AOM, §05-09-20, Contaminated Runway Takeoff Performance — No significant change, they simply fixed two placeholders that said "cross reference" instead of the actual link that got by the editors for Revision 3.

AOM, §05-09-30, Contaminated Runway Landing Performance — There were several "cross reference" broken links here too. But there were a few things of note:

  • The text used to recommend calculating landing performance using contaminated runway distance data for standing water if weather conditions included heavy rainfall only for EASA operators, it not applies to us all.
  • The text used to specify a 115% additive when landing on contaminated runways; the mention of this in §05-11-30 is now used for this.
  • The landing distance factor table (Table 6) now simply sends you to the appropriate section for the needed factors.
  • The recommendation for landing distance factors used to cite Advisory Circular 25-32 but now simply refers you to the limitations section of the AFM.
  • The text makes note of the fact braking performance is given for autobrakes HIGH or OFF, depending on the runway condition and flaps, with corrections provided for other autobrake settings.
  • The paragraph that notes "If the HUD Flare Cue is displayed during a landing on a wet, standing water, slush, dry snow, wet snow, ice or compacted snow runway, no further landing distance additive is required" now includes instructions on how to get the flare cue display using the HUD/EVS tab of the TSC.
  • The Landing Distance Contaminated Ruwnay, Flaps 39°, Single Thrust Reverser Operational now has a second page, allowing corrections for temperature, the contaminant, and speed additive.

G500 AFM Rev 4

The big things here are the change of the pre-takeoff wing anti-ice limitation from three minutes to four and a new rejected takeoff procedure. Not everything that has been changed is on the list of changes page and not everything with a Revision 4 on the page has been changed. The administrative process is a bit lacking.

Post by: ja1

Posted: 16 September 2019

AFM, §01-03-10, Types of Airplane Operations Permitted — The operation "/I and /G special FMS procedures operations" has been deleted. The ADS-B Out section now says "The installed ADS-B out system complies with EASA CS ACNS Supgart D section 4 (ADS-B Out)."

I am not sure what the /I and /G special FMS procedures are. I initially thought they meant the Block 10 flight plan codes for IRS and GNSS but the fact they've been deleted brings this into question.

AFM, §01-03-20, GVII Temperature Operating Envelope — The minimum temperature for ground start has been lowered from -20°C to -40°C.

AFM, §01-27-20, Degraded Control Law — added "Takeoff is prohibited when operating in a flight control law mode other than Normal (Alternate, Direct, or Backup)."

AFM, §01-30-20, wing Anti-Ice — revised the restriction to read "Wing anti-ice shall be selected on at least 4 minutes prior to setting takeoff power."

AFM, §02-04-10, Taxi — revised the caution to read "Wing anti-ice shall be selected on at least 4 minutes prior to setting takeoff power."

AFM, §02-05-30, Descent — The procedure was to select wing and cowl anti-ice systems when entry into icing is "imminent" but now it says "anticipated."

AFM, §02-06-60, Quiet Shutdown — The old procedure assumed the APU was already secured, the new procedure mentions this explicitly as Step 1.

AFM, §02-08-60, Fuel Balancing in Flight — A note used to say correcting fuel imbalances less than 400 lbs is not recommended. Now it says "Under normal operations, do not balance fuel unless it is near, or above, a limit stated in 01-03-80, Maximum Fuel Imbalance."

AFM, §02-08-100, Departure Airport not in FMS Database — The procedure now walks you through the needed FMS entries.

AFM, §02-08-110, Arrival Airport not in FMS Database — The procedure now walks you through the needed FMS entries.

AFM, §02-08-130, High Crosswind Takeoff Procdure — The procedure now specifies applying the brakes prior to adding thrust, but it appears to have a mistake in that it asks you to set "throttle" prior to brake release instead of "throttles."

AFM, §03-16-150, TSC Blank or Unresponsive — The procedure is the same, but now it applies to a blank or an unresponsive TSC, as opposed to just a blank TSC.

AFM, §03-20-30, MAU / MRC / NAVCOM Overheat — The requirement to descend to 35,000 feet or below has been deleted.

AFM, §04-19-80, Rejected Takeoff — This new procedure codifies what you already knew: throttles - idle, wheel brakes - apply maximum, thrust reversers - apply maximum. Once you are clear of the runway, get into the appropriate checklists.

G500 PAS Rev 3

On the surface of it, this change can be summarized by one thought: the G600 has been certified. The entire PAS bears "Revision 3 (Re-issue) July 15/19" on each page because the title of the manual now includes the G600. Specifically, it says "GVII-G500/G600 Production Aircraft Systems" on each page.

But on the last item shown here, p. 14-18, there is something very big. More about that . . .

Post by: ja1

Posted: 28 August 2019

PAS, p. 2-35 reflects the standardization of the internal baggage compartment door limitation which requires it remain closed above 45,000 feet. (The old restriction in the G500 was 40,000 feet.) Curiously, p. 2-50 forgets about this and still has the old restriction.

PAS, p. 6-19 adds column headings to the flight control mode comparison chart.

PAS, p. 6-23 adds column headings to the pitch and roll control normal / degraded active / passive chart.

PAS, p. 9-7 catches up with cowl anti-ice restrictions: "During ground operations above 15°C, cowl anti-ice operation is inhibited with an engine operating above 72% N1, and CAI will be auto inhibited on ground with TAT > 15°C with an engine operating > 72% N1"

PAS, p. 9-29 adds column headings to the WAI OFF and ON engine idle chart and adds a referercne to the AM for engine vibrations in icing conditions.

PAS, p. 2-32 adds a bullet point about vibrations in icing conditions.

PAS, p. 14-18 completely changes several concepts with flight idle and changes what was called "WAI Idle" to "FIKI Idle." The term "FIKI" does not appear in any other GVII publication that I have. (I've asked the question and have the answer in the next pararagraph.) It also formalized what we used to call "KOZ" (Keep Out Zone) into what it now calls the "NDZ" (No Dwell Zone).

From ASC No. 022: "This service change improves engine response and reduces cabin effects during severe Flight Into Known Icing (FIKI) encounters. EEC software version and replacement of the compressor inlet cone optimizes the aircraft engines providing greater protection for operations under icing conditions. Items addressed by this update include: Changes to No-Dwell Zone (NDZ) and flight idle schedule to improve performance during icing; Burner Pressure (PB) limits to protect against over-thrust due to Total Air Temperature (TAT) inputs; Improved N2 threshold for rotor bow abort; Thrust setting updates for increased fan tip clearance."

I've heard that in severe icing the engines can produce noises during ice shedding that can be heard in the cabin. This doesn't happen often (I'm told only 4% of the time under these conditions) but often enough to do something about it. The problem occurs while we are transiting through 41 and 46% N1 during FIKI. To counter this, starting with Block 1 and ASC 022, they have increased the weight of inlet cone on the engine and the FADEC has been modified to allow a smooth reduction or increase of thrust through the NDZ by use of engine speed averaging. Let's say you are at 47% N1 on both engines and need a little less thrust, something that could be achieved by reducing both engines to 44% N1, right in the middle of the NDZ. The FADEC will bring one engine to less than 41% N1 and keep the other above 46% N1, perhaps setting the left engine to 41% N1 and the right to 47% N1, for an effective average of 44% N1 on each. I am told you will be able to see this on the engine instruments but the effect should be transparent if you aren't watching the engine instruments closely. So now you know about FIKI. I imagine this will be explained a bit better in future issues of the PAS.

Radar Course

Post by: mb1

Posted: 28 August 2019

The GVII radar is a marvelous piece of technology which is also used in the GVI. Here is a good way to learn about that radar:

G500 AOM Rev 3

There is clearly something odd about this change. The list of changes on the "Highlights for Revision 3" page includes pages that were from earlier revisions. AOM, §01-01-90, Flight Controls Check, for example, is identical but the page says REVISION 3 and the change bars would have you believe the entire procedure was rewritten, but they are identical. This is true for several items. You would believe QFE operations are completely changed, for another example, but they are identical to Revision 2. Some of the pages with REVISION 3 on the bottom right have not been changed, some of the pages with revision bars are from earlier changes. So I've ignored all that and only included what appears to be changed since Revision 2.

Post by: ja1

Posted: 3 August 2019

AOM, §01-01-40 now has you check oxygen pressure when doing the crew oxgyen mask check.

AOM, §03-01-30 adds extensive guidance on starting the APU during cold weather operations if the airplane has been cold soaked.

AOM, §03-01-40 adds a section about external engine heating if attempting an engine start when engine oil is at or below -30°C and it has been less than 8 hours since shutdown (because of rotor bow).

AOM, §03-01-50 adds several steps to engine starting procedures when the oil temperature is less than -30°C.

AOM, §03-01-90 removes the requirement to check TAT probe agreement during lineup/taxi during cold weather operations.

AOM, §03-02-10 revises Holdover Times tables and moves them to the front of thsi section.

The revisions page says AOM, §03-02-40 says Temperature Compensation has been added but it is identical to Revison 2 except for an added note that tells us that FMS values modified by Temp Comp calculation are shown in cyan when pending activation; they are in green once activated.

G500 AFM Rev 3

Revision 3 of the GVII-G500 Airplane Flight Manual is dated July 16, 2019, just four days shy of the one year anniversary of the original publication. There are a few changes to consider here.

Thanks to group member dh1 for summarizing much of this change, which I've added here. He also notes that there is a new quiet shutdown checklist and that the new Brake Energy charts are more realistic.

Please note there are also revisions to the AOM and PAS; I'll get to them next week.

Post by: ja1

Posted: 1 August 2019

AFM, §01-02-10 used to say "Takeoff Crosswind Limits, Normal Takeoff - 30 knots." Now it says "Takeoff Crosswind Limits, Static Takeoff - 30 knots, NOTE: For crosswinds above 30 knots, refer to 02-08-130, High Crosswind Takeoff Procedure." That added procedure has you set 57% N1 until 20 knots and then MTO. That adds 500 feet to our required field length. This implies there isn't a limit for a rolling takeoff. A similar change is made to AFM, §01-71-20.

AFM, §01-03-10 imposes a long list of required equipment for RNP AR approaches. The change marker would lead you to believe is is just the item "3 Display Units" but it really than entire column.

Several of the limitations rename "Flaps 39°" to read "Flaps Down" which is a throwback to earlier Gulfstreams. You just have to realize that having your flaps set to 10° or 20° are not flaps down. This affects your maximum flaps altitude (AFM, §01-03-30), maximum flaps extended speed (AFM, §01-03-40), maximum load acceleration (AFM, §01-03-50), and throughout the manual where Flaps 39° is used.

AFM, §01-03-90 is added to require the SAFO 19001 1.15 minimum landing distance safety factor to your unfactored landing distance.

AFM, §01-12-30 states explicitly "The use of fuel additives is not required." The section with acceptable APU fuel is gone so the paragraph and table number is different. There is still a table of approved fuel additives, but it is Table 3 now.

AFM, §01-12-50 gives us a new limitation for minimum ambient temperatures for refueling operations: -40°C for Jet A1, -30°C for all other approved fuels.

AFM, §01-22-30 prohibits you from taking off with any RAD Alt failure unless you have ASC 17 (EEC software update) or ASC 22 (which is another update scheduled for this fall).

AFM, §02-02-10 Has you check fuel quantity and the CMC during the Airplane Power Up check for a 500 lb. fuel discrepancy.

AFM, §02-05-10 recommends retracting flaps to 10° when above 400 feet AAL and accelerating through 400 feet AAL and delaying selecting flaps up until accelerating through 200 KCAS during performance limited takeoffs.

AFM, §02-05-20 recommends the FMS fuel quantity not be updated in flight.

AFM, §02-05-50 says that flaps must be set to 20° prior to selecting flaps to down.

AFM, §02-06-30 says we should delay 5 seconds between shutting down engines to reduce the likelihood of a break power transfer.

AFM, §01-30-40 prohibits the selection of TAT probe heat with either engine running.

AFM, §01-30-50 prohibits the use of anything but Type I for deicing.

AFM, §01-32-10 the tire check after two hours stationary limitation has been removed.

AFM, §01-34-40 prohibits the use of ASC 001 TOLD if ASC 022 (EEC is installed. I'm not sure about this one.

AFM, §01-35-20 changes some oxygen limitations. The warnings about passenger masks not providing sufficient oxygen for prolonged operation above 34,000 feet and prolonged operation above 25,000 feet cabin altitude with passengers aboard not being recommended are deleted. There is a new limitation: "The passenger oxygen system shall not be used for periods exceeding 15 minutes above 25,000 feet cabin altitudes."

AFM, §01-71-10 removes the thrust reverser 30 seconds limitation.

Changes to AFM, §03-01-20 and AFM, §03-01-40 remove some information about a dual pack failure; it used to tell you that the cabin will climb to 8,000 feet in 3 minutes at normal cruise altitudes.

AFM, §03-04-30 has changed the Left Main AC Bus Fault procedure quite a bit.

AFM, §03-07-40 has changed engine vibration in icing conditions procedure.

AFM, §03-14-20 and 30 give us new fuel imbalance procedures.

AFM, §03-17-10 adds steer by wire fail considerations to the landing gear failure to retract procedure.

AFM, §03-17-20 revises the landing gear failure to extend procedure.

AFM, §03-20-10 has simplified the Forward Floor and/or TRU Hot procedure, eliminating the need to go CPCS Semi as a first step. §03-20-20 does the same for the EER Hot / PDB Overheat procedure.

AFM, §03-21-20 adds a caution to the Dual Bleed Air System Failure procedure that tells you that the cabin will climb to 8,000 feet in 3 minutes at normal cruise altitudes. §03-21-40 does the same for the Dual Bleed Air Hot procedure.

AFM, §03-21-50 has you going to idle on the affected engine for a Bleed Pressure High - Single CAS message.

AFM, §03-21-100 revises the CPCS Failure procedure.

AFM, §04-06-20 revises the Engine Failure above V1 procedure.

AFM, §04-06-30 revises the Dual Engine Failure procedure.

AFM, §04-08-20 revises the assisted airstart procedure. Of note: the engine could begin a windmill start on its own but will transition to an assisted start once the start switch is pressed; so don't delay hitting that switch for more than 5 seconds. The windmill airstart now has a procedure of its own in §04-08-30.

AFM, §04-21-30 corrects an error to say an EDM is armed anytime airplane altitude is at or above 40,000 feet, and adds consideration for passenger lighting.

AFM, §05-04-10 explains that it isn't necessary to limit takeoff grossweight in an emergency return landing put you above the tire limit speed of 224 mph (195.5 KTGS) if you land without a VREF additive, but if you do to recompute using a chart added for that possibility.

Parts of AFM, §05 are modified to add climb gradient penalties for en route climb with ECS on and to limit stall reference speeds for landing at Brake Energy limited weights.

AFM, §5A and Appendix A1 are added for performance with ASC 22 installed (New EEC software

AFM, Appendix A has you check Brake Energy limits if your BTMS temperature is greater than 80°C prior to commencing takeoff using reduced thrust.

There are other changes, but not really that significant in my view.

High Cabin Temperature Requires Manual Temp Control

Post by: st1

Posted: 15 July 2019

Added to: G500 Air Conditioning System

We had to manually control the aft cabin temperature recently. Turns out the temp sensor behind the aft facing seat across from dIvan became disconnected behind the side panel and gave an incorrect cold temp reading. The actual temp in back was in high 70’s, the temp sensor was saying 50f, and duct was 160f before selecting manual. Manual mode allows direct valve positions shown as a percentage for conditioned air rather than setting a temp in auto, pic attached. As soon as we selected manual we were able to get a comfortable temp in the back after a few adjustments. At our destination FAST techs found the issue and reconnected the temp sensor. We haven’t had any issues since.


Photo: Aft cabin manual temperature control

Click photo for a larger image


Photo: Aft cabin temperature sensor

Click photo for a larger image

Servicing Engine Oil Using Ground Service Bus Only

Post by: st1

Posted: 9 July 2019

Added to: G500 Powerplant

If you look at the Frequently Asked Questions section of the Gulfstream GVII manuals you will see this one: "Can I remotely replenish my oils and hydraulics on the G500?" The answer is yes, "if you select the main batteries ON and the Ground Service Bus switch ON." In previous Gulfstreams all you needed was the ground service bus, for this one you need both. Why? We asked the guy in charge of the system at Gulfstream and here is what he said:

"At one-time Rsvr Qty Left and Right were wired to RDC 20. Program said we needed redundancy so we split off and wired to RDC22 for the Right System. Unknowing at the time, RDC22 is not wired for GSB. As such, not available for replenishment via the Replenisher System on the ground with aircraft powered down. At the time we realized, the design was mature and to reconcile would take wiring changes as well as re-allocation of RDC's. Program at that time opted not to pursue the change. Since then, it has come up again and PR015301 was initiated on 10.04.18. It is still shown as in "Root Cause" and classified as a 3A (Significant Negative Impact). Since is still as "Root Cause", I do not know what the impacts are for the change nor the time frame to implement."

We hear there is a program change request to fix this, but for now you need the battery switch on as well as the ground service bus.

Temporary Certificate Valid Dates

Post by: GM2

Posted: 9 July 2019

Added to: GVII Regulatory Notes

Keep an eye on the validity of your temporary certificate. The FAA has had a backlog of issuances and mine will expire in a few weeks. I just requested a new temporary from FSI today as the airman registry does not show the GVII type yet. FSI called the FAA and apparently the FSDO must and has signed off on the issuance, but the document is in the mail back to Oklahoma City and the FAA quarantines incoming mail for three weeks to avoid threats. I know one January and one February airman that have received theirs but an earlier (November) airman just received his within the last couple of weeks. Just a heads up.


Gulfstream GVII-G500 Aircraft Operating Manual, Revision 4, August 29, 2019

Gulfstream GVII-G500 Airplane Flight Manual, Revision 4, August 29, 2019

Gulfstream GVII-G500 Production Aircraft Systems, Revision 3, July 15, 2019

Revision: 20190924