B777 Undifferentiated or Other Model
Flight Crew Last 90 Days 100; Flight Crew Total 18500; Flight Crew Type 5500
Communication Breakdown; Confusion; Situational Awareness; Workload
ATC Issue All Types; Deviation - Altitude Crossing Restriction Not Met; Deviation - Altitude Excursion From Assigned Altitude; Deviation / Discrepancy - Procedural Clearance; Deviation / Discrepancy - Procedural Published Material / Policy
General None Reported / Taken
Human Factors; Procedure
I have safety concerns over the design and use of the MSCOT 3 RNAV Arrival at Houston and would appreciate if this report can be sent and shared with the ATC QA personnel in the Houston Center for their review. Please share with [Company] ATC Specialist - whoever is in the best position to represent [the Company] and its pilots to discuss these concerns with Houston ATC. There were no altitude or speed deviations on this arrival; but I want to share my observations and concerns so others can study the poor design and better understand the complexities that pilots have in receiving or accepting this arrival. It is my intention to share this data so that this procedure and others like it can be improved before they become a problem or turn into an actual pilot deviation. There are too many gotcha's on this arrival and it is primed to set up the pilots up for failure or a deviation.While inbound to IAH we were cleared to 'descend via' the MSCOT 3 RNAV Arrival with the DIESL transition.  We were talking with Houston Center. The IAH ATIS at the time was advertising arrivals on Runway 27; 26L; and 26R. The primary concern when receiving the clearance to Descend Via the MSCOT 3 arrival was the fact that ATC did not issue a runway assignment with the clearance; so there was no validation for the pilot to know what the 'Bottom Altitude' should be based on the ATIS or the Jeppesen Chart. IAH does have a NOTAM that indicates pilots on the MSCOT 3 arrival should expect RWY 26R; but this is a poor way to communicate the plan. I think I misunderstood which controller would have this information for us; which contributed to my mistake and set up my expectation bias. The Jeppesen chart needs to have the NOTAM information printed directly on the chart instead of using a standing NOTAM (7 months and counting). If the runway assignment won't be known until much later on the arrival; then the STAR should be redesigned to end with out having different waypoints and altitude clearances based on an unknown or unconfirmed runway assignment.  Personally; I do not think there should be a multiple choice for bottom altitudes on an arrival. I think they need to simplify these arrivals and publish very plainly a 'bottom altitude' that is applicable for the arrival. I would suggest that the individual runway approach charts (example - ILS 26R; ILS 26L; etc.) be updated with appropriate transition legs and fixes that lead from the arrival and transition to the approach. These transitions should begin where the STAR ended and can then be runway specific. It is much easier to simply have to select a runway with the appropriate transition then have to start over by reselecting the STAR; STAR transition; approach; and approach transition; especially when you have already flown 3/4ths of the arrival and you're no longer at the starting point on the arrival. Additionally the approach does not include the fix where the STAR ended. On this Arrival it would be better designed to end at an IAF for the Approach. This arrival ends with a Radar Vector to the approach. In my suggestion; the pilot would fly the arrival to a common ending waypoint; and a common bottom altitude; and would be in a much better position to receive a further runway assignment at this point. It would make it easier if the pilot's further clearance would include clearance to fly an applicable transition as part of the approach. They can design lower or expected altitudes for any of the waypoints specific to the assigned approach after you have transitioned from the STAR to the approach chart. For RWY 26R; it would be nice to design an additional IAF starting from DOMNO with route and altitude constraints published on this approach chart. It would be much easier for the TRACON controller to clear the aircraft on the intended route leading to the approach. A sample clearance with a redesigned approach chart could be something like: 'after DOMNO you are cleared for the ILS 26R approach; descendVIA the ILS 26R DOMNO transition.' For pilots not familiar with Houston; trying to look at the chart; apply applicable NOTAMS; understand or anticipate at what point the actual frequency change to TRACON will occur and not make any mistakes is very challenging. Note #5 on the top of the Jeppesen STAR says: 'Expect runway assignment from Houston TRACON upon initial contact'; which is what we were expecting. What is not obvious is the fact that you are talking with Center throughout the majority of this arrival; and you are not actually talking to TRACON until the very end of the arrival. When starting our descent into Houston we were still with Center (128.075) versus TRACON. I queried the ATC Controller; and the response back was that they did not have the runway assignment yet. I further questioned the controller; explaining that for me to be able to descend via this arrival I needed to have a runway assignment so that I could correctly program the bottom altitude in to both our FMC and to the altitude selector on our mode control panel. I made a mistake for not applying the NOTAM. If I had correctly applied and understood the NOTAM; we would have programmed in RWY 26R and we would have used 6;000 Feet as our bottom altitude. The note on the chart that indicates to expect a runway assignment from TRACON did not register correctly with me. After questioning the controller on which runway to expect; I got further confused when the controller came back and stated that it says on the approach chart to use Runway 26R for planning purposes. This was incorrect information. No one in our crew could find this note on the arrival chart (STAR); so we are not sure what chart the controller was referencing. Perhaps I overlooked this; or perhaps Jeppesen needs to add this note to the 70-2J chart. The Controller should have mentioned that there is a NOTAM; which explains to plan for the RWY 26R. After discussing this; we agreed to set up and plan for RWY 26R. With the crossing restriction set to SKLER at 6;000 feet. We were instructed to contact Houston Approach (TRACON) on 120.65. As I recall; we checked in with him still descending via the MRSCOT 3 arrival for RWY 26R (this implied that we were descending to a cleared altitude of 6;000 feet). Our position at this point was just past DOMNO and we were currently descending through 7;000 feet in both LNAV and on VNAV path. The controller said we could expect RWY 26L if we wanted it. We agreed and accepted RWY 26L. Immediately upon accepting the change to RWY 26L; I re-set the altitude in our MCP for 7;000 feet and advised the controller that we were climbing back to 7;000 feet. The MSCOT 3 RNAV Arrival shows 7;000 feet as the bottom altitude when using RWY 26L. We descended to approximately 6;850 feet by the time the descent was stopped and the climb began back to 7;000 feet. The controller then stated that it was not necessary to climb back to 7;000 feet; and cleared us to maintain 6;000 feet.  There was quite a bit of confusion in the cockpit at this point as we were not clear as to what our cleared route our waypoint should have been. About this point; we read back that we were descending to 6;000 feet; but I missed the waypoint he had cleared us to fly to as it was not yet programmed in our [FMC] because we just received a runway change; so the data in our FMC was not matching what the controller was trying to give us. Sensing through the lack or my correct readback. ATC must have sensed my confusion and he give us a heading to fly. That simplified everything as we now simply flew a 090 heading; which was a downwind leg and continued at 6;000 feet. From there we received radar vectors and further descent to fly the approach to Runway 26L.What I would like the controllers to understand are the following points:1. It would be best if we knew the runway assignment upon the receipt of this Arrival; and prior to receiving the Descend Via Clearance.2. If the above is not possible;I would suggest that this Arrival be re-written so that it simply shows the last altitude at DOMNO between 10;000 feet and 8;000 feet. That way there is less of a chance the pilot will descend to the wrong altitude.3. The controllers need to understand that our briefing and programming of our FMC's - are best done prior to starting the arrival. It is optimal for the pilots to brief the anticipated approach prior to starting our descent from cruise altitude; but here is an example that prevents the pilots from knowing which runway is anticipated or should be briefed until much later on the arrival. Once established on the arrival; any changes to runway and STAR transitions require not only new selections in the FMC; but it also requires the pilot to go in and re-sequence the legs page so that the correct active waypoint remains active; and the subsequent fixes are correctly sequenced. Doing a last minute change is much more demanding and should be avoided if possible.4. The speed restriction note that shows to transition from Mach to 280 knots should be listed differently. Not sure how this can be done; but I can tell you from experience that it will be very easy for pilots to miss this note. No excuse if a pilot misses it; but the human factors involved with the way it is presented on the Chart make it very easy to overlook. 5. NOTAMS should not be used as the permanent correction to a charting error or a procedural error. NOTAM 2061/14 was issued on 18 SEP 2014; which states to add note: Fly the Runway 26R transition Houston Approach Control may assign a different transition on initial contact.  6. The chart date was revised by Jeppesen on 2 Jan 2015; which leads me to the question of why the NOTAM was not incorporated into this publication update. Why are we relying on NOTAM's to correct mistakes on Approach Charts that have been standing there for almost 7 months? 7. I would like to emphasize to the Controllers that getting a runway change late in the arrival process requires multiple FMC updates; pilot briefings which only lead to confusion and increase the risk of a pilot deviation. In this case; we received the new runway assignment after passing DOMNO. This required us to go into the FMC and re-select the Arrival along with the new runway. However; before being able to execute the new information into the FMC; the pilots need to re-sequence the waypoints so that it correctly shows the active waypoint that we are navigating to. This combined at the same time of an altitude change due to a new runway assignment is just simply setting up the pilot for failure. It then requires the pilots to brief the new approach while in a very busy part of the arrival.
B-777 Captain makes some excellent points in describing the challenges facing flight crew flying the MSCOT RNAV arrival into IAH.